Archive of Our Own ^beta

Chapter Text

Day 1 :

Shadow sat in complete silence, the night chill settling deep into his fur after thirty minutes of being stationary. He was currently waiting for the go-ahead so that he could make his way across the clearing he was lurking in the shadows of.  

Where is he? How long does it take to disarm a few robots?  

The island felt eerily too quiet. No sounds of animals or nature filtered into his advanced hearing. Just silence.  

They had got news a week ago that multiple Eggman facilities had been located on this island, with intense energy readings drawing around. There were only a handful of things that could cause such readings and he was one of them.  

The Chaos Emeralds.   

Team Dark had originally been stationed here to find the emeralds, nothing out of the ordinary for them. However, they had bumped into them along the way. That blue hedgehog could never stray far away from trouble, even if he tried (Shadow didn’t think he tried). Within moments of finding Team Sonic, had their entire plan gone down the drain.  

So that’s why he found himself here now. Sitting in some uncomfortable bushes in the dead of night. And although logic told him that it made sense for him to be working with the blue hedgehog, that they made a good team, he couldn’t help but be a little bitter about being separated from Rouge.  

“I’m needed in the skies, it’s where I work best. You’ll just slow me down.” she had smirked at him.  

The idea of him slowing anyone down was laughable. But he accepted defeat, and so he just had to wait. Wait. Wai-  

“OK, uh, you might wanna start moving like right-” came the tinny voice through his communicator.  

In the distance the muted sound of an explosion causes Shadow’s ears to twitch, the smell of smoke making its way across to him.  

“Right now! Right now, would be good!”   

With a sigh, Shadow thumbed over the Chaos Emerald in his grasp and teleported to their arranged meet up point. He had about two seconds to take in his surroundings (smoke, gunfire, several dozen robots running amok) before is vision was full of a blue blur.  

“You made it! Ok, change of plan-”  

“What happened here, Faker?”  

“Well, you see this giant robot over there,” he pointed to something that vaguely resembled a mix between a mech suit and a tank, stamped with the signature Eggman logo, “yeah that’s where the emerald is. But be warned-”, They both suddenly ducked as a hot wave of fire washed over them, “Fire robot.”  

“Nothing can ever be simple with you.” Shadow groans, readying himself for the fight.  

“Well, where’s the fun in that?” he grins, saying goodbye with a quick wave before spin dashing away to take out some of the stragglers.  

The fire robot of doom is hardly the worst robot he’s ever thought, and he doubts it will be the last on this island, but he makes quick work of it either way. Once he gets the fire jets disarmed, he easily makes his way to the entrance of the tank structure, tearing the door off its hinges.  

“There you are.” he muses as the Chaos Emerald comes into view, reaching down to grab it. By the time he returns back to the ground, Sonic is waiting for him, not a hair out of place as he stretches in the night.  

“Easy peasy. What’s next? Killer ice robot? Thunder eel?”  

“We’re going back to the safe house. We need to contain the emerald.”   

And without another word, Shadow is grabbing Sonic by the arm to teleport them back.  

Shadow lands on his feet easily, moving to place the Emerald out of sight. Meanwhile, Sonic lands with a stumble, wobbling slightly as he takes in his changed surroundings.  

“You know I hate when you do that.”  

“That’s why I do it.”  

“Asshole.” the hero muttered under his breath.  

After a quick debrief with the team they learn that there are a few more Eggman UNITS for them to raid, with 3 Chaos Emeralds still unaccounted for. Rouge’s voice comes through tinny, “We heard news of potential movement in around 9 days, towards the main Eggman HQ. We stopped a few bots on the way there.”  

“OK, so we need to gather the remaining three emeralds and rendezvous at the HQ in 9 days?” Shadow inquires.  

“Exactly. See you then.”  

Shadow hung up with a sigh, looking over to where Sonic was currently lounged on the communal couch of the safehouse, not a care in the world.  

It was going to be a long 9 days.  

Day 3:  

Something wasn’t right.  

It had been two days since the hedgehogs had been left to clean up the remaining UNITS on the ground and find the emeralds.   

Fine. That was all fine.  

As much as Shadow hated to admit it, they worked well together. Even if the blue hedgehog often ran face first into most situations and could never be bothered to listen, or follow the plan, or-  

Whatever.  

It was fine. Shadow knew what to expect from Sonic. He knew Sonic.  

So then, where was this feeling of dread creeping in from? As if his fur was covered in damp, sending chills down his spine. The pounding in his head- When had that started?  

A few times now he’d had to blink a mist from his eyes so he could focus on his tasks, and not the flush that was radiating across the back of his neck.  

The worst part? Shadow knew exactly what this feeling was.  

His damn Black Arms biology. The biology that was obsessed with reproduction, despite Shadow’s utter lack of interest in it. All Shadow knew was that two times a year for around five days he would suffer.  

A splintering headache, chills, fever, pains in his joints, brain fog, and in the worst times even sickness. The worst part had to be the sudden mood changes.   

Shadow is self-aware enough to see that he’s not always the “friendliest” person on Mobius, but the effect of this situation never failed to humiliate him. It was all because of the need . So unbearable, every time.  

And he knew just how to fix it, but he wouldn’t. He’d rather groan his frustrations into a pillow or his hand because he hated how his own brain debased him, taking away his own autonomy, his choices, just to feel relief.  

So then, why now?? Why now when he was stuck with him .   

They had made good progress in the last two days as they raided the UNITS on the island, even managing to bag a chaos emerald along the way. But Shadow was on high alert, working tirelessly to appear normal when really all he wanted to do was curl up onto the floor and rub friction across his sensitive skin.  

And that idiot wasn’t making it any easier for the agent. No, he was always so close, his natural and fresh scent suddenly overwhelming and no matter how much Shadow tried to keep his distance he would find himself lingering close enough to catch it anyway. Plus, Sonic was always so... friendly. He should have grown used to it by now, but a sudden hand clasping his shoulder or flicking one of his quills never failed to make him flinch from the touch. And he never missed the sly and proud grin shot his way if the other caught his reaction.   

Right now, they were sat at the safe house, looking over the map that the fox had sent them, highlighting potential other areas for them to investigate. Sonic was sat lazily on the couch next to him, sprawled out as he hummed a tune and checked his communicator idly.   

Too close too close too close  

A frustrated huff must have left Shadow’s nose because suddenly the other hedgehog's attention was on him, a brow quirked.  

“What?”  

“Did I speak?” he growled out, trying so hard to focus again on the map, but Sonic was sat so close and his hand was draped across the back of the couch close to his burning nape.  

“Well, obviously you’re in a mood about something ! You’ve been glaring alllllll morning, even more than usual.” Sonic whined, forgetting about his communicator and turning to face the other, “If it’s about me accidentally eating your leftovers, I SAID I was sorry, man.”  

Shadow kept his mouth shut, teeth biting into his tongue to take his focus away from the growing tingle vibrating under his fur. Leftover food was the least of his problems right now, not when he could feel his fangs threatening to draw blood.  

“Are you ignoring me?” Sonic gasped, leaning closer, “Wow, real mature. You know-”  

Too close too close too closetooclosetooclose- 
closerclosercloser 

Shadow stood with a start, his knees knocking the table with the force of throwing himself forward.  

“We need to go. We don’t have much time.”  

With that he sped out the door, leaving a confused Sonic to scramble up after him and out the door.   

Something wasn’t right.  

Sonic just didn’t know what.  

There was something different about Shadow. Sonic had thought he had a pretty good idea of the black hedgehog’s behaviours by now, after all they had worked together before. In fact, Sonic prided himself on just how well he knew the other hedgehog, likely better than most.  

Glaring a hole into one spot and tense quills meant he was uncomfortable, but not necessarily angry. A small smirk on his tan face paired with crossed arms usually meant he was happy, probably pleased with himself after a race or fight. A lip curled into a snarl, a sharp fang flashing, eyes impossibly red. Angry.  

But this? Sonic wasn’t so sure anymore. It was almost as if the other was... scared? Or in pain, maybe? His shoulders were hunched, his fur lacking its usual shine, quills bristled as if he’d been running his claws through them in frustration.  

So, he’s sick, then? And he’s just too stubborn to mention it?  

This guy...  

So, Sonic decided to make a conscious effort to keep an eye on the other, watching him carefully for any signs of hurt. But Shadow was making it so hard to do even that. The GUN safehouse they were using was very simple; a small living area with a mini kitchenette attached, one bathroom and two small bedrooms. Whenever Shadow wasn’t forced to talk logistics with him, he was hiding away in the bedroom, only coming out again in the morning.  

It was on the start of day 3 that Sonic noticed just how sluggish the other was moving. It took him a long time to arise from his room, legs almost dragging behind him, slowly putting on his air shoes and blinking at them as if they were a foreign item to him.  

Sonic couldn’t stay quiet anymore, placing a careful hand on Shadow’s shoulder to steady him, “Whoa, man, are you o-?”  

A hiss, as if being burned rung out between them as the other pulled away in a flash.  

“I... I’m fine. Don’t... touch me.”  

Uh-Oh, snarled lip, fang, red eyes. He’s angry.  

The blue hedgehog backed off, not wanting to antagonise him any further.  

“OK! OK... Just, let me know if you need anything. You don’t look great.”  

“Gee, thanks.” The agent rolled his eyes in exasperation as he exited the safehouse, but there was no real energy or bite in it.  

OK Sonic realllyyyy wanted to just leave the other to brood alone and suffer whatever illness was plaguing him.  

But he couldn’t.  

Especially not right now as they entered the final UNIT of the day. Things had been going great; broken down a few robots and found a sealed chaos emerald. Great! But as Shadow had taken the emerald suddenly, they were surrounded. Sonic had turned his back for only a moment to deal with a few by himself, smiling widely as they fell to the floor in defeat, but his glee was short lived. The sound of choking snapped him out of his reverie, spinning around to see Shadow held up in the air, the firm metallic grasp of a vice around his neck.  

Sonic made to move forward but the telltale static of chaos energy stopped him in his tracks and a second later a chaos blast disposed of the robots. However, Sonic watched in shock as that sluggishness from the morning returned, Shadow swaying on his feet as he tried to regain his balance.  

“Shads!”  

He fell to the floor, a pained shout unlike anything he’s heard from Shadow before echoing in the UNIT.  

“Shads? Are you OK?!”  

The hero knelt close, not wanting to touch him, yet his anxiety rose as the other failed to get back up, just lying on his side, panting as if there wasn’t enough air for him to take.  

“Shads, c’mon you’re scaring me.”  

There was something about seeing someone who boasted about being The Ultimate Lifeform laid unresponsive on the ground that put a dark pit in Sonic’s stomach. Why couldn’t he get up? Maybe this illness was more serious than he thought?   

I’m so stupid I should have checked in earlier and made him stay home it’s all my fault -  

Without thinking, Sonic picks up the Chaos Emerald that lay by their feet. How did this work again? He’d only used Chaos Control by accident before.  

“Uhh... um... Chaos Control?”  

The feel of the hardwood floors of the safehouse hitting his knees sent a shock through his system, blinking the blind spots away.  

“Yeah, gotta work on that landing.”  

Next to him, Shadow still lay curled on his side, small groans leaving his mouth. His fur looks damp as if coated in sweat, his fangs scratching cross his lips to leave red welts on his muzzle, eyes misty and dark.  

“Shadow...”  

Sonic gently grabs Shadow’s arm, almost dragging him to the couch and sitting him there.  

“Sonic...” Comes his gravelly voice, “You have to go.”  

“Go? Go where? You obviously need help-”  

“No. I’m fine,” A pained sigh as he leans his head against the back of the couch, “I’ll be fine. You can’t stay here.”  

Sonic huffs from where he’s stood in front of the couch, hands on hips, “Stop telling me what to do. You owe me, tell me what’s going on. Now.”  

One of Shadow’s eyes cracked open, “You’re... You’re not going to like it.”  

At this the hero grinned, “Oh yeah? Try me.”  

Shadow seemingly glared up at the ceiling for a while, his quills bristled in defence – Oh uncomfortable! - and for a moment, Sonic believed he was just going to ignore him until he caved and left. Just as he was about to ask one more time, Shadow spoke up.  

“It’s something to do with my... biology.”  

“OK... what does you being a mysterious alien have to do with you looking like you’re about to keel over?”  

“The Black Arms put a lot of value in... production. Especially reproduction. It’s so important that even my body is built to accommodate this... need.”  

“Reproduction...? So, like-?”  

“Yes. It’s exactly as you’re thinking.” Shadow continued to glare at the ceiling, obviously unhappy to be having this conversation with is rival of all people. The only other person who was aware of this problem was Rouge and few select members from GUN.  

“So, what? You need someone to help you out?” At this Shadow’s head whipped around, a look of pure shock and confusion marring his face and the hero so wishes he could frame it, “You made me think you were dying and all this time I could have just lent a hand??”  

“No. I don’t... need a hand. I can and will do it alone, like I always do. That’s why you need to go. I’ll be ready before the rendezvous.”  

“I don’t know, Shads. It looks really painful. Isn’t there some medicine you can take or... something?”  

“No. Everyone who I could ask about it is... dead.”  

“Can’t I help at all? I want to if I can.”  

This got a raised brow from the other.  

“Don’t be stupid. You have no idea what Black Arms cycles entail. I don’t even know. It’s better if you go.”  

“But I won't.” Sonic moves closer, cautiously kneeling onto the couch at Shadow’s side as if not to spook him, “I want to help you. I couldn’t leave knowing you’re hurting like this. Not very hero-like, y’know.”  

“Forget it, Sonic. I won’t allow it.” Then he was up, moving towards the bedroom.  

“Well, I’m not leaving! And you know where I am, if you need me!” Sonic yelled through the now closed door between them.  

Day 4:  

He was on fire. His skin was on the verge of melting from the bone, his fur soaked in sweat and clouding his vision as he writhed on the bed. An almost continuous snarl was forcing its way out of his mouth, his jaw clenched with the will to try and subdue it.  

You can stop this. Just reach down and   

No.  

It would pass. This was just one of the many waves he would have to swim against, the current always felt strong but he had always prevailed before. He could do it.  

But he’s right outside. I could ask him. Take him. He wants me to-  

With a growl Shadow grips at his quills, pulling at them in frustration to stop his mind wandering to the hedgehog just on the other side of the house. The need is spineless, feeding on his lucid wants, exaggerating them to get what it wants.  

He knows you so well. No one else can help you it has to be him it has to be-  

It’s fine. It was only day 2 of this torture, he still had maybe one more lucid day in him. Maybe he could convince Sonic to go before then. He doesn’t want anyone to see him like this, so vulnerable, so pathetic.   

Sudden relief snaps him back to attention, looking down to see his own hand grinding over his pouch urging his dick to poke through the slit. Gaia why did it have to feel so good. Mindlessly he takes himself in his hand, stroking slowly from root to tip, careful of the ridges and bumps that line his shaft.  

Breed. Claim. The relief.  

Distantly he can feel himself drooling into the pillow under his head, hips raising to increase the friction and pace. He knows he must be panting, and he knows he must be doing it loudly, but he’s past the point of caring. The only thing that matters is the relief .  

The head of his cock is leaking slick, coating his hand and fur with his own mess, easing the glide of his hand as it rubs over the sensitive head. As he strokes, his mind wanders back to yesterday, the way Sonic had offered himself so easily, like he wanted to lend him more than a hand.  

A grunt leaves Shadow’s mouth as he thinks of what would have happened if he had said yes , would Sonic have reached over and palmed him like he’s doing to himself now? Would he know how to stroke just right under the head of his cock to make his thighs shake? He’d probably know just how to get him worked up, to have him leaking over his hand. Would he go for a taste-  

Imagine how good he would be for you. He knows exactly what you need.  

Before the vision could get any further, Shadow was moaning into his pillow as he came, feeling the base of his cock swell as his knot hit nothing but his own first, pumping furiously up and down to milk himself.  

He lays there, panting, cum coating his stomach and hand, basking in the little relief he can catch. But then he feels it. The fire, creeping in again through his muscles. Threatening to scald him from the inside out, the anger and frustration rising back up.   

He lays there for long enough that his dick returns back into its pouch, but the bulge never goes away. He’s going to have to do this again and again and never stop for maybe 3 more days, he can’t bare it he-  

A knock at Sonic’s door rouses him from his sleep. A quick look at the clock in his room tells him it’s only 5am. For a moment he thinks maybe he heard wrong, Shadow was never awake this early, even when he decided not to sleep. He was content to ignore it and started to doze again, but a thud from the living area caught his attention.  

Someone was definitely out there.  

Hesitantly, Sonic opened the door, his eyes scanning the communal area of the safehouse. Nothing was out of the ordinary, well, except for the hedgehog sat limply on the couch. Sonic noted that the other also wasn’t wearing his gloves or air shoes, just simply sitting on the couch with his head resting on the back, a deep furrow in his brow and eyes closed.  

“Sonic.”  

He startles slightly at his name, moving slowly into the living area.  

“You’re still here.”  

“I told you I wouldn’t leave.” Sonic chided with a tsk.  

“I... I need help.” came the muted reply.  

Sonic almost missed it, straining his ears to try and understand what he was talking about.  

“What?”  

“Did you mean what you said? About... helping?” The black hedgehogs voice almost sounded timid, as if he couldn’t believe himself that those words were leaving his mouth.   

Sonic came to a stop by the couch, kneeling very slowly next to Shadow.  

“I meant it. I want to help you, Shads. Really.”  

Shadow didn’t reply, just resting there with his eyes still closed.   

Sonic’s hand hovers over a black knee, waiting for any rejection before bringing his hand down to pet the soft fur there, his fingers smoothing it down in gentle circles. A hiss escapes Shadow’s mouth, neck craning back as if to savour the touch.  

“Sonic... I don’t know how much longer I can give you warnings... the need is too strong; my mind is not my own sometimes when I’m like this. It’s all instinct. I don’t know how you’ll be affected, how-”  

Sonic continues smoothing down the ruffled fur of Shadow’s thigh, “I’ll be fine. Actual reproduction isn’t possible for me, contraceptives y’know.” A lopsided grin spread across his face as Shadow opened his eyes and regarded him, “Let’s focus on you, hm? There’s only five days until the rendezvous. I’d hate for them to see you like this.” Sonic pouted.  

Shadow watched him carefully for a moment, as if trying to see any underlying message in his words. Sonic could feel the minute tremors of Shadow’s thigh under this hand, growing by the second.  

A small huff. And then in almost a gasp, “Sonic... please.”  

“OK, I got you.”  

Sonic moves to place his bare hand high on Shadow’s thigh. The small tremors still vibrated under Sonic’s fingers as they danced higher and higher, skimming across the firm hard bulge of Shadow’s pouch. A jolt flashed through the other, an almost strangled sound leaving his throat as he focused his eyes on green ones.  

“Just a question. How uh... Lucid are you going to be during all of this.”  

“The first few days are usually OK. Today you can control the pace. But by tomorrow I will be functioning on mostly instinct.”  

“Noted.”  

Sonic continued his gentle pawing at the hard pouch, palming over the slit with a finger and encouraging the wet head to peak out. “C’mon big guy.” Sonic cooed, not being able to help himself as he leant forward to press his mouth against the fur of Shadow’s shoulder to hide his excitement.  

A few more minutes of thumbing at the pouches slit and Sonic felt the heavy weight of his full-length slide against his hand. He peered down, curious to see how the Black Arms differed from other Mobians.  

God, he was thick, especially at the base and so long. It was flushed a flattering shade of dark pink, but the thing that caught Sonic’s eye the most were the series of bumps and ridges lining the shaft.   

And he was so wet, the tip practically oozing a continuous stream of slick over Sonic’s fingers as they stroked softly. Without thinking, Sonic brought his hand up to lick away the wet from his fingers.  

All the while, Shadow watched him with a dark look in his eyes as Sonic’s tongue tasted him, hesitantly at first before reaching down to collect more and taste again.  

“You taste good.” Sonic groaned, smile lopsided as he licked his lips clear.  

It was true; almost like a sweet and soothing essence that left a slightly salty aftertaste and coated the inside of his mouth like honey. He couldn’t get enough. Just as Sonic was about to reach down to sample more, gloveless fingers tilted his chin back to regard him again.  

He could distantly feel some of Shadow’s slick making the fur on his muzzle wet and sticky, accompanied by the sound of Sonic’s fingers rolling wetly over the head of Shadow’s dick as if to milk him of more. His eyes felt glassy as his senses became dominated by Shadow . Wasn’t he supposed to be doing something?  

“Greedy,” the other murmured, bringing the peach muzzle closer to his own, “let me taste too.”  

Peach lips met tan, pressing softly against each other with a hum. 
What if inside here tastes just as good? 

Sonic’s tongue was licking across the seal of Shadow’s mouth a second later, desperate to get another taste. The black hedgehog opened his mouth willingly, groaning as an eager tongue joined his.  

The first thought that Sonic had as they kissed was, he’s sweet here too , but that was derailed by the more urgent thought of long!!! , as Shadow’s long tongue invaded his mouth.  

Sonic hiccupped as his tongue traced over the roof of his mouth, threatening to go further down his throat before backing off. Sonic pulled away with a gasp, hazed eyes searching for crimson, smirking when seeing the other just as dazed as himself.  

“Mmm, more.”  

That brings Shadow’s attention back to the present, eyes focusing on the hedgehog before him. Still kneeling on the couch beside him, tail wagging and smacking the couch in his excitement. Sonic’s thighs are closed tight as he squirms under the other’s gaze.  

“Poor thing,” Shadow whispers into a twitching ear, pushing on a round peach chest until they fall back with Sonic below, “let me help you.”  

“Aren’t I supposed to be helping you?”  

But the thighs below him still spread on their own, allowing him to take his place between. 
Touchtouchtouchtouch- 

He tries to shake away the demanding need to take and claim what’s his, using a moment to breathe so he can savour the view below. Sonic, ears pressed low on his head, legs wide, showing off his usually hidden slit.  

God, he’s so wet .   

Shadow traces the line of the slit with his bare finger much like Sonic had done to him. Where he expected to find a hard mound, his fingers instead spread the slit to reveal the wet, pink folds hiding beneath. The round clit had escaped its hood, begging for attention.  

Shadow’s mouth watered at the thought of running his tongue along those folds, dipping inside to really taste him, but a different need in him was growing and he wanted to do this while he was still semi-sentient.  

A finger rolling over his swollen clit brought Sonic back to attention, his body relaxing deeper into the couch as he was rubbed in tiny circles.   

“Ohhh yes, Shad-ah!... Just like that.” he whined, rolling his hips in encouragement.  

“Do you want my fingers?”  

“Yessss.”  

Shadow circled around his hole, teasing and watching as it clenches around nothing, “Where do you want them?”  

“Inside! Inside me, please.”  

A long groan left peach lips as two fingers push inside, the wet noises making him blush as Shadow picks up the pace, his own slick wetting his fur. Sonic moans loudly, mouth wide and hips angled as he tried to take more. Every brush of those clawed fingers against his sweet spot has his toes curling into the couch, vision blurring as he races to the finish.  

No! It’s not enough. Need it inside, that sweet taste inside too.  

He must have been whining for a while because Shadow’s pace falters to ask him what’s wrong, but before he can open his mouth Sonic is moving. In a flash, Shadow is on his back, watching in awe as Sonic straddles over him, back turned and ass on full display before he’s sinking down without a care. A small snarl escapes Shadow at the idea of being pinned, but the feel of Sonic around him snaps him back.  

“Sonic- Fuck!”  

“So good... so full... more.”  

He bottoms out quickly, his wet pussy more than enough prep to take Shadow. His hips begin moving as if in a trance, raising up to slap back down hard.  

“Good boy,” Shadow groans, hands finding purchase on blue hips to pull down and meet his thrusts, “you’re taking me so well.”  

“More, please.” Sonic cries, looking back over his shoulder, eyes wet and glassy, pupils blown.  

Shadow obeys, watching in interest as the ridges on his dick catch around the hole, rubbing along his sweet spot perfectly. Drool drips from Sonic’s lips down into his muzzle as his hips keep moving, desperate to milk all of that sweet taste out.  

“Mmm! Ah! Inside... I need it!”  

“You’ll get it. You’ll get all of it.” Shadow soothes, stroking his sides reassuringly.  

The base of his dick starts to get tighter, the size beginning to swell as his knot grows. It catches around the wet folds, drawing out a guttural groan from the hero as he grinds back against it, using it to stimulate his clit.  

A few more thrusts and the knot pops inside before slipping back out.  

“Full...” Sonic keens as the knot slips back inside to lock them together.  

Shadow’s thrusts become shorter as he grinds the knot as deep as it will go, his own mouth hanging open as he pants into the open air, hips jerking to keep them together. This was so much better than his hand, his knot was meant to be inside tight, wet, heat. His body tenses for a split-second before he’s spilling inside the warm heat above him.  

He’s barely done enjoying his own release when he suddenly jolts in shock as something wet splashes onto his pelvis, Sonic gripping tight around him. The dirtiest moan he’s ever heard bounces off the walls of the safehouse, the hedgehog above him hips rolling in mindless circles to draw out his own orgasm.  

He squirted?  

The black hedgehog watches in awe as the hero shakes above him, trembling like a leaf as his pussy keeps clenching around the knot, pulling more groans from himself.  

Sonic pants loudly, struggling to stay upright but locked in place by the knot. Shadow moves upright slowly until they’re back to chest, laying them down sideways on the couch. He noses at the others neck, inhaling his scent and unconsciously licking his own into damp blue fur.  

“Sorry, but we’re going to be stuck like this for a while.”  

“...’s fine... sleepy.”  

“Get some rest. We’ll talk later.”  

“M’kay.”  

And so, Shadow was left to stew with his thoughts, all the while holding his rival in his arms. The need had simmered down, but he knew it would return and by tomorrow it would be unbearable. He’d likely have no control of his emotions, working purely on what his body thought felt “right”. They definitely needed to talk more later.  

There was also something at the corner of Shadow’s mind, thinking about what he had just seen from Sonic. He had never seen him look so dazed and mindless... it was if he was under the influence of something? Maybe the Black Arms biology was more potent than he thought.  

Shadow wanted to ponder further while he was lucid, yet sleep won.  

He could explore it further tomorrow.  

Chapter Text

Day 4 (2):  

Sonic awoke to hands wrapped around him and the feel of a body still behind him, except now he recognized the interior of the room resembled a bedroom. A sly sniff of the cotton beneath him alerted him to the fact it was likely Shadow’s room, this new scent finally bringing him out of the fog that had settled over him.  

What even was that? It had felt like he’d been encased in warmth, his senses muted but his skin so sensitive. And that taste ... He had enjoyed it a little too much. A wild blush slowly crept over his muzzle and across his neck at the thought of what had happened earlier.  

When Sonic had offered to help (and he really did want to help), he hadn’t predicted that his excitement would get the best of him. Sure, that strange fuzzy feeling had clouded his brain around the edges, but Sonic is sure that at least 80% of his actions were from himself. It was as if all the common sense and decency in his body had decided to take a vacation, giving his body free reign to do as it pleased.  

Gaia, why can’t I do anything nonchalantly...? He’s gonna know I-  

Images of him flipping the agent over to ride him flashed through his memory, how good it had felt, how amazing Shadow had looked under him. Something in his chest warmed at the possibility of no one else seeing Shadow the way he had yesterday, an almost undetectable purr vibrating once through him.  

The feel of a nose finding its way under his quills to rest in the juncture of his neck had him fully alert, the perpetrator taking their own sniff of his scent and humming to themselves. Sonic melted into the hold behind him, allowing the other hedgehog to nose along his neck.  

“You’re awake?” came the deep voice, murmured into the fur there.  

“Mmhm.” he sighed.  

Shadow pulled himself away slowly, leaning over to make eye contact, “We should talk. While I’m able.”  

Sonic rolled over to face him, taking in his sleepy expression and messy quills. He had never seen the other like this.  

“How are you feeling, Shads?”  

The other mulled the question over for a while, “I’ve been worse. I don’t have long until the next wave hits me. I just want to warn you about a few things.”   

“Like what?”  

“Once my cycle really hits, everything I do will be on instinct. It might be hedgehog instinct; it might be Black Arms instinct. I don’t get to choose.”  

“OK... hedgehog instinct I know. Grooming, scent marking, being defensive, biting.”  

“But the Black Arms instincts are different. Claiming. dominating... breeding.” Shadow almost whispers the last part.  

“Hey, I told you. You don’t have to worry about... that. Just do what you need to do, Shadow. I’m pretty certain I won’t mind either way, if it’s anything like earlier.”  

“About that,” Whether Shadow had noticed or not, his hips had been moving in a small muted circle against Sonic’s thigh that was resting between them, the firm pouch rubbing slowly against blue fur, “I noticed yesterday, after you tasted... Me, something was different.”  

Sonic dragged his eyes away from the show below him, forcing the blush that wanted to spread along his cheeks down, “Oh, yeah. You taste great, by the way, so I’m not complaining.”  

“Right. Well. I think that maybe what happened is you came into contact with an aphrodisiac. Making you crave it.” Shadow’s hips were still moving on their own, the pink tip of his cock slowly starting to peak out.  

“Oh? So, what, you’re giving off some kind of pheromone that makes me want to ravish you?” A chuckle.  

“Perhaps,” the agents eyes flutter as he grinds harder, “Probably to make it easier to... to breed you.”  

“Mmhm,” Sonic’s hand comes to rest at the back of Shadow’s neck, drawing his attention, “do you need some help there?”  

At this, Shadow’s eyes flutter again, as if trying to make Sonic’s words form a sentence that he could understand. Instead of replying verbally, he nods his head slowly as his hips move closer to rub his now fully exposed dick against Sonic’s leg.  

“I’m taking that as a yes.”  

Sonic reached down between them to wrap his hand around the long shaft, stroking firmly as he continued to watch the other hedgehog. His lips had curled into a lazy smile, eyes unfocused as he chased the feeling of release.  

He was once again leaking all over Sonic’s hand, the slick sounds sending shocks to Sonic’s clit as he thought about how good he must taste again.  

“Wow, you’re so wet. I bet you’d slip right in.” Sonic cooed, using the hand still at the back of Shadow’s neck to draw him closer, “I bet you’d like that, huh? To come inside me again?”  

Unable to vocalize just how much he really wanted that, Shadow opted to press his mouth against Sonic’s instead, wasting no time to press his tongue against the others. As their tongues kissed, drool wetting both their muzzles, Sonic’s hand increased its pace, taking his time to rub over the ridges on the underside.  

He was rewarded with sweet groans, hummed straight into his mouth. Sonic fought against closing his eyes, wanting to take in the whole sight of Shadow while he was like this. Shadow whose hips were chasing Sonic’s hand whenever it pulled away for a second. Shadow with his mouth hanging ajar, letting Sonic simply lick into his mouth as he pleased.  

“You’re so hot. You don’t even know what you’re doing to me, Shads.” Sonic whined, squeezing his thighs together to try and calm the pulse between his own legs, “I’m going to be thinking about this for a long time. Every time I rub myself. Every time I put my fingers inside, I’ll be thinking about you.”  

The blue hedgehog notes the thickening of the knot at the base of Shadow’s cock, taking the time to close his palm around it on the downstroke.  

“Mmm, I can’t wait to feel this again, too. You’re gonna give it to me, right?”  

“Yes.”  

“You promise?”  

“Yesyesyes.”  

It’s not long before Shadow’s groans increase in volume, his hips tensing as he nears the end. Sonic’s hand moves faster, watching in awe as Shadow’s cock begins to spill onto his chest, wet pants hitting the fur on his neck.  

“That’s it, there we go.” Sonic hums, smiling as the other goes limp in his hold, melting into the pillows as his orgasm passes.  

Without a second thought, Sonic is moving his mess covered hand down between his legs, fingers sliding over his exposed clit that is begging for attention. A sweet sigh leaves his mouth as he rubs small circles over it, staying true to his word and thinking about how good Shadow had just looked.  

“Shadow... Shads, yes.”  

The wet sounds from his fingers fill the room, the mixture of both their mess giving him enough lubricant to increase his pace. Then, slowly his fingers inch down, circling around his twitching hole-  

A strong grasp around his wrist stills his movement, snapping his eyes open to see Shadow almost glaring at him. Before he can even voice his annoyance at being stopped, he’s being tugged and the word “Up” is growled.  

Sonic finds himself straddling over Shadow’s stomach, before two strong hands grab onto the backs of his thighs and move him higher up, his wet pussy just inches from an open mouth. In a second, those strong hands are pushing down his hips, his clit making direct contact with the warm suction of Shadow’s mouth.  

Sonic’s thighs immediately tense around messy quills, his hands scrambling to find purchase on the wooden headboard in front of him. Shadow’s tongue flicks daintily at the swollen bud, warm and persistent shocks radiating through his core all the way down to his toes. The blue hedgehog doesn’t even try to be quiet, loud whines escaping his mouth as that long tongue makes its way down to his hole.  

The tongue teases for a moment, dipping in just to get a taste, a groan vibrating through him as Shadow finally gets a sample of Sonic. The tongue moves further in and just when Sonic doesn’t think he can go deeper, he does.  

“G-gah! How- how long is that thing?” He pants, grinding down to get more , paying no mind of the rest of Shadow’s face, “So deeeeeep.”  

Shadow’s fangs threaten to scratch against Sonic’s folds, a reminder of just how deep he is as his tongue flicks over the warm inside, drinking in as much of the blue hedgehogs slick as possible. Possessive hands keep Sonic pressed down hard on his face, Shadow not needing to come up for air even once.   

The repetitive flicks of his tongue over the spongey surface inside almost drives him mad, his eyes rolling into the back of his head after one stroke in particular. And Sonic is loud , his voice alternating between pants, cut off whines or full-blown moans.  

“You- You’re gonna make me cum! I’m gonna-”  

Shadow takes note of the thighs trembling around his head, angling his head so that the tip of his nose can find its target, rubbing hard circles into the hero’s clit. It only takes a few rough licks to Sonic’s sweet spot and a well-timed rub of his nose to have Sonic lifting his hips slightly, his slick squirting down onto Shadow’s tongue and chin.  

Shadow works him through it, swallowing down his reward and savouring the taste as the other sways above him, overstimulation threatening to take over. The agent lifts up Sonic’s hips fully, removing his tongue, but keeping him close enough to stroke his tongue around the wet folds and thighs, grooming him.  

Sonic shivers and shakes above him, knees threatening to give out but the other rolls him over onto his back before he can crash down. Shadow then takes it upon himself to continue grooming the other; cuddling close to lick over the sweaty fur on his forehead and neck, moving over to his chest to suckle gently on his pebbled nipples, his fangs scratching lightly on his chest with each stroke.  

“Ahn... I love your weird alien tongue.” Sonic sighs dreamily, stretching his arms above his head to give the other more space as he alternates between them.  

“Mmm, it has its perks,” Shadow smirked against peach fur, lifting up to lick across peach lips and kiss into Sonic’s mouth for a moment, “we should bathe.”  

“You’re no fun. You just cleaned me.” Sonic pouted.  

Shadow ignores him to pull away, tugging on the others leg to get him to start moving, “There’s only so much a tongue can clean.” he huffs, “Let’s go while we have the chance. I know I certainly won’t be able to in the next few days.”  

With a sigh, Sonic follows behind to the shared bathroom, moving to sit on the side of the tub while Shadow began running the water. He became too impatient to wait for the water to fill to tub, so opted to just sit in the water, resting his head on his knees as the sound of running water sent a sense of calm through his body.  

Eventually, he heard the water cease running, followed by the sound of another body joining him in the water. They both sat in silence for a moment, before Shadow let out a short huff and murmured, “Turn around.”  

Sonic grumbled but did as he was told, allowing hands to smooth over his quills with something that smelt musky, and then water was cascading over his shoulders as Shadow rinsed it off and repeated the motion.  

“Shadow, I have a question,” the other didn’t speak, but Sonic took the silence as a cue to go ahead, “how long have you been experiencing these, uh, cycles?”. Shadow remained quiet, to the point that Sonic thought he was just going to ignore him. Maybe it was a sensitive topic? Regular Mobian’s didn’t experience anything even remotely similar to this, so Sonic truly had no reference frame. Shadow’s fingers began massaging something into Sonic’s fur, likely an oil of some kind, his fingers playing with the tips of his ears and pulling a small purr from the hero.  

“It started a few years after I came out of statis.”  

“That must have been kinda scary for you.”  

“More confusing than scary. Humiliating. Debilitating.”  

Sonic took this time to spin around, “Your turn,” but instead of allowing Shadow to turn, he just simply moved closer, slotting his legs over Shadow’s hips and reaching his hands around to clean his quills. He took extra care to clean where he knew he’d soaked the agent earlier.  

“Did you get anyone to ... help you, you know, before now?” Sonic didn’t want to admit the anxiety that swirled in his stomach at the thought of someone else seeing Shadow the way he had in the last 24 hours.  

Shadow’s eyes searched his face for a moment, but the hero avoided his gaze, focusing on the task of putting Shadow’s quills back into position.  

“No. I did it alone.”  

Sonic worked hard to hide just how pleased he was to hear that, distracting his hands with the oil the other had used to begin massaging it into the spot between Shadow’s ears.  

“Well... you know I’m always glad to help. So.”  

“Right. Let’s see how sure you are after the cycle ends, hm?”  

Their silence resumed as Sonic continue to rub the clean smelling oil into Shadow’s quills and fur. As he moved his hands down to massage around Shadow’s neck, that’s when he noticed just how tense the other hedgehog was, the strain on his jaw, the furrow in his brow.  

“You’re hurting?”  

“No. I’m fighting about every voice in my body right now not to bend you over the side of the tub.”  

The words sent a jolt straight through Sonic’s core. It’s then that Sonic notices how close said core is to Shadow’s own pelvis.  

“I don’t think you should ignore that.”  

“I think we need to get out of the tub.” Shadow said with a deep breath.  

They exited the bathroom after drying off, Shadow hastily moving away to the small kitchenette so he could grab something quick to eat. Sonic took the opportunity to grab a handful of different snacks and scarf them down. As he passed the couch on his way back to the bedroom, he noted the wet stains there with a blush, taking a small detour to the bathroom to grab a few towels in order the save the bed from further damage.  

It was as he was organising some of the towels down on the bed that he felt someone drape themselves flush over his back, a muzzle nosing at his neck before fangs nipped at his nape in warning. Sonic paused on his hands and knees, waiting to see what the next move would be. Strong hands found their way into his thick quills, getting a firm grip before moving Sonic’s head further down into the pillows, leaving only his hips up.  

Something wet smeared across the fur on the back of a thigh, a pleased groan vibrated into his skin. The wet sounds of skin on skin sounded for a moment as Shadow’s hand moved, before suddenly the hand had found its way to his mouth, two fingers covered in the agent’s slick pushing into Sonic’s mouth.  

The second that taste hit his tongue again, Sonic was keening, opening his mouth wider to let the fingers go deeper, wanting to swallow all of it. The fingers moved in and out of his mouth slowly for a while, coating his mouth with the salty sweet essence of Shadow before leaving his mouth and moving to spread his slit apart.  

“I bet I don’t even have to prep you, you’re already so wet .” Shadow sighed into his neck, spreading the mixture of Sonic’s spit and slick through his folds until they met his hole. Two fingers found their way inside at once, dragging a low sound from Sonic’s lips.   

It was hard to think now that the warm fog had begun to creep over him, muting his senses and only allowing him to feel the way Shadow’s fingers were rubbing over his sweet spot with increasing speed. He felt his knees spread wider to give the other a better view of just how desperate he was, clit sitting exposed to the air and untouched.   

“Oh my g- more!” he drawled lazily, his tongue feeling tied from the effort it took to make a sentence.   

Shadow added another finger to the mix, meanwhile his other hand still gripped tightly into Sonic’s quills, pulling occasionally to send a jolt down his spine.  

“How many fingers can you take, Sonic?”  

“F-four. Please, more.”  

“You get what I give you.” came the growl behind him, “And you’ll thank me for them.”  

“T-Thank you.”  

A pleased hum came from the other as he added the fourth finger, adding a twist of his wrist to really cover every inch inside of Sonic. Distantly, Sonic could feel the drool leaving his mouth to pool into the cotton of the pillows, but his primary care at the moment was to get Shadow inside as deep as possible.   

As he was distracted with the movement of Shadow’s fingers behind him, he didn’t notice the hand from his quills move until once again two fingers were forcing his mouth open and coating his tongue with Shadow’s slick.  

“Since you like the taste so much.”  

A garbled “Thank you” came from around the fingers as they pressed deeper, threatening to breach his throat but pulling back to safety before Sonic could gag. They repeated a pattern of moving deep into his throat, before pulling back to rest behind his teeth again and again.  

“You’re gonna come just like this. On my fingers.”  

An almost pained whine left the hero at the thought of not getting what he really wanted, earning a smug laugh from the other.  

“Greedy.”  

Without any warning, Shadow’s pace increased tenfold, the four fingers fingering Sonic’s pussy dragging incoherent moans from Sonic’s throat, the momentum of him thrashing around on the bed causing him to finally gag on the fingers currently down his throat. Instead of pulling back, Shadow holds him there, waiting for him to swallow around them and recover. Sonic feels the rapidly approaching release swimming around the base of his stomach, tingling through his core all the way to his toes.  

Shadow watches in amusement as Sonic’s tail wags rapidly, showing just how much he’s really enjoying himself. Suddenly the fingers have left Sonic’s mouth to stroke up the underside of his tail, short claws sending shivers down his spine. Shadows strong hand grips onto the tail to steady it, earning a shout from the hero as he’s pulled back forcefully onto the fingers behind him repeatedly.   

It's with a muffled and wet cry that he finally cums, his knees scrambling on the bed as his body stiffens, back arching to push his hips further back onto Shadows hand as it continues its fast pace. Just when Sonic is about to cry out again, both hands are gone and suddenly he’s falling completely onto the bed.  

Before he can even blink away the fog that continues to numb his head, a hand is rolling him over and he feels his legs being spread and knees aligned with his own shoulders, bent and held at the back of his thighs. Shadow looks at the mess below him; the blue hedgehog with drool matting his muzzle, not a trace of his usual smug grin, but instead mouth openly panting and eyes lost in a haze. His dick twitches at the sight, not even hesitating to reach down and spread his pussy again.  

Shadow can feel something almost possessive creeping over him like a blanket, not entirely sure that it’s only his instinct acting. Here he has the hero of Mobius, spread out on his bed and waiting for him, looking at him with half-lidded eyes in anticipation. Shadow traces his thumb over the round clit that is just begging for attention, almost grinning with pride when Sonic bites his lip and starts to move his hips to grain more friction.  

No one else should have the pleasure of seeing him like this.  

Sonic blinks back into reality at the feel of Shadow pushing inside straight to the hilt in one smooth slide, every single ridge working to push Sonic into overstimulation. A punched-out sound leaves his mouth as Shadow’s hips begin working, the smack-smack-smack of him hitting Sonic’s backside resonate through the room as the pace increases.  

“You take me so well, Sonic – Fuuuuck!” Shadow’s eyes look ready to cross as he pants, head tilted back and tongue threatening to loll out of his mouth at any second, “It’s like- hhhh you were made just for me , to be taken by me. Only me.”  

Sonic let Shadow know just how much he liked the sound of that by squeezing tight around him, both of them gasping at the tightness. Shadow’s fast pace halts suddenly into a slow deep grind, the tip of his cock rubbing just right against the edge of Sonic’s cervix continuously. The new stimulation ripped another orgasm from the hero, his toes curling where they hung in the air by Shadow’s head and his eyes rolled back as slick gushed from him and onto the towel he had managed to place earlier.  

He came to realise that the other hedgehog was still thrusting into his hole, pace undeterred by Sonic’s new overstimulation.  

“Shads... I can’t...”  

“I’m not done with you yet.”  

“T-Too much-”  

Shadow ignored his cries, pressing Sonic’s knees down flat by his shoulders, giving him better access for the knot that was starting to form. Despite the overstimulation, Sonic couldn’t stop himself from trembling in anticipation as he felt the knot begin to hit at the entrance of his hole.  

“Yessss.” he slurred, feeling Shadow press a smirk into his neck.  

As the knot slipped in for the last time, Shadow’s thrusts turned into circular grinds as he chased his own release, finally tipping over the edge as Sonic’s overstimulation crested into his third orgasm. A dopey smile graced the hero’s face as he felt the warm feeling of Shadow spilling into him, mixing with his own slick and going deep.  

“’s good Shads.” he sighed, finally content and relaxed, fully giving way to the mist surrounding his head as a purr rumbled through him.  

Shadow’s own little pants danced across his chest, his tongue absentmindedly licking across peach fur to soothe the other. Even after his orgasm, Shadow’s cock continued to occasionally pump his spend into Sonic while they were locked together, drawing out little sighs of pleasure as they waited.   

Sonic was still way too high on whatever was in Shadow’s slick to care about much of anything except being full and being cleaned by the other. Whenever Shadow’s tongue would pause its grooming of his fur, the hero would let out a soft whine to encourage the other to continue.  

Eventually, Shadow pulled out, both of them grateful for the haphazard towel under them as cum leaked out of Sonic. Using the edge of the towel he cleaned up what mess he could from the hero before moving up between still spread legs to peer down at the other. Sonic was looking more coherent, face morphing into a lopsided smile as he wrapped him arms around Shadow’s neck and purred loudly.   

Shadow leant down to kiss the hero, hands coming up to hold both sides of his face as he licked into his mouth. They made-out sloppily for a while, the room full of the wet sound of their mouths connecting and little hiccups from Sonic’s enthusiasm.   

As Shadow’s tongue traced the roof of his mouth, Sonic realised just how much he did not want to stop kissing Shadow, maybe ever. No one else’s tongue was ever going to compare after this. Something cold ghosted over Sonic at the thought of what would happen after this cycle finished; would they just return to their normal routine? Would Shadow even acknowledge what had happened in the safehouse? Sonic squeezed his eyes shut harder, distracting himself with the sloppy kisses Shadow was giving.  

After a long while, Shadow pulled away, rolling Sonic onto his side and slotting himself behind, their bodies not leaving even an inch of space. It was with a heavy arm over his waist like a brand, tongue still cleaning over his sweaty nape and the sound of purrs that carried Sonic off to sleep.  

Day 5 had continued on in much of the same fashion; Shadow was becoming noticeably more possessive of his time with Sonic, unhappy to be spending more than five minutes apart. At one point, Sonic had ventured into the small kitchenette to scavage some snacks to keep him going, only to find himself bent over the breakfast bar while Shadow thrust into him as if starved. He had barely slunk down onto the tile floor before the next round had begun.  

An almost permanent snarl graced Shadow’s face unless he was deep inside his favourite rival, teeth often threatening to bite through blue fur.  

On the 6 th day, Sonic’s eyes blinked open in confusion, wondering what could have stirred him so early. The sun was barely peeking through the blinds yet, the red numbers of the clock reading only 5:32am. A strong huff of warm air against his ear brought him to attention, allowing him to take in multiple things; a vice-like grip of a hand on his hip to hold him in place, loud panting, and finally something wet brushing between his thighs, catching just shy of his own slit.  

A bleary look down and Sonic see’s the shiny head of Shadow’s cock poking out from between his thighs, before his hips pull back and it disappears again. Sonic’s head rolls back with a groan at the sight, “Shads, you’re killing me here.”  

With a fight against the grip on his hip, Sonic manages to wiggle down slightly, waiting in anticipation for the next forward thrust to brush against him. Shadow’s dick makes contact with the increasingly wet folds in front of him, him showing his appreciation by biting into the space of Sonic’s neck.  

Sonic’s hips tremble against the hold, wanting so desperately to grind back against the other and create more friction. A few well-timed thrusts against his clit see’s Sonic shaking down from a muted orgasm, his eyes fluttering closed as he waits out Shadow’s own release. The feel of warmth making a mess between his thighs and folds finds him a few moments later.  

More than ready to simply fall back to sleep in this position, Sonic blinks tiredly as Shadow moves from the warm spot behind him. The hero’s thighs are parted and the feel of that warm tongue sends a jolt through him. It licks languidly over the mess between his thigh's first, sucking little kisses there before moving up to slowly comb over his slit. Again, lips suction around him as Shadow’s cum is sucked into his own mouth, driving the hero crazy at the thought.  

The warm body between his legs moves up slowly, leaning over on his elbows and using one hand to grip Sonic’s chin firmly. With his mouth already ajar from his pleasure, it takes nothing for Shadow spit the contents of his mouth straight into the blue hedgehogs. He holds it there, waiting, while Shadow regards him with blank and almost zoned out expression, as if he’s not even in control of himself.   

Instinct.  

A few seconds pass and then Shadow is moving again, hip lips crashing down as he kisses the other with no shame, them both swallowing the mess they’d both created. The lightheaded feeling crashes over Sonic again, his ears pinning low to his head in submission while his legs part on their own. Waiting.  

“You’re not done cleaning yet.” Shadow murmurs, motioning down to himself. His cock stands hard between them, still covered in cum and Sonic’s slick. The agent moves slowly to sit at the edge of the bed, and Sonic knows what he’s expecting.  

The hero crawls off the bed to kneel on the floor, finding his spot between Shadow’s knees easily. His mouth almost waters at the thought of getting a direct taste of Shadow, drool pooling at the corners of his mouth as he leans forward.  

Shadow watches with a cool expression as the other’s lips press onto the head, tongue dipping into the slit where pre-cum is beading almost immediately. The wet tongue follows the path of cum down the shaft, teasing around the ridges to clean him off, sending little shocks down his spine. He watches with pride as Sonic’s tongue flattens itself over his teeth before suckling the tip into his mouth, as a whine of relief escapes him once he gets that taste again.  

Such a good boy.  

“You love it don’t you? You’re addicted... to something only I can give you.”   

Sonic looks up to meet his eye before mumbling, “Yea,” with his mouth full.  

Shadow can’t get over how cute he looks like this, with his eyes unfocused and mouth wrapped around him tightly, only caring about getting what he wants. Sonic’s head moves down inch by inch, his tongue swiping around the shaft as he sucks carefully, dead set on getting another load down his throat.  

The urge to push Sonic down is almost maddening, his hands twitching at his sides where they fight against the will to just push him down to the base and hold him there, to feel him struggle until he’s ready to cum down his throat.   

One of Shadow’s hands finds its way into the mussed blue quills, slowly pulling the warm mouth off.  

“Sonic... Let me use your mouth, I promise you’ll get what you want. Be good for me.” Shadow groans at the look of pure bliss on Sonic’s face, mouth open and drooling down onto his muzzle as he listens.  

“I can do it, don’t go easy on me. I know how to do it, please.”  

A small fire ignites in Shadow’s chest, threatening to curl his lip into a snarl at the idea of Sonic doing this for literally anyone else. He fights against the growl rumbling in his chest, watching as blue ears flatten again in response. Shadow’s hand guides the waiting mouth back down, giving him maybe a few seconds to adjust before pushing down further.  

He feels the head of his cock rub against the tight suction of a throat, teasing himself with a few mini grinds before pushing down again on blue quills. Sonic’s breath sounds rapid as he gets accustomed to the feeling of being almost choked, fighting against the urge to gag as his nose presses into the black fur of a stomach.  

“Yesssss. That’s right, good boy.”  

Sonic preens at the praise, his tail starting to wag fast, his eyes fluttering closed as he waits. Shadow simply takes his time to enjoy the warm, wet and tight heat around him, fighting a losing battle against his instincts to claim every inch of his new cycle mate. His second hand comes up to hold the other’s head still as he grinds as far as he can against that mouth, his vision almost going white at the feel of Sonic gagging around him. The tightening of his knot forming only adds to the pleasure.  

Shadow pulls back briefly to let Sonic gasp for some air, before pushing straight back into the start of where his knot is, establishing a slow and deep pace.   

“This is mine. Your mouth was made for only me, to stay warm and tight around my cock for as long as I tell you.”   

A long hum vibrates down his shaft as Sonic voices his agreement, eyes opening briefly only to flutter closed again.  

“All of you is mine. Do you understand, Sonic?” Another hum, “Your hole is mine, for me to breed. To stuff you full of my knot. My pups. Would you like that?”  

At this a whine sounds, his head nodding as much as it could with both of Shadow’s hands gripping onto his quills. It’s then that Shadow notices the movement of Sonics hips and hand, rubbing circles over his clit.  

“Dirty hedgehog. Does it get you excited, thinking about being full with my pups, huh?”  

Another nod.  

“I’ll give it to you. I promise. I’ll show everyone that you’re mine.”  

The known fact that Sonic was on contraception meant nothing to the two of them in the moment. The only thing that mattered was Shadow suddenly increasing the pace of his hips, using his hands to pull the tan lips against him with each thrust, ripping little gags from his throat that sent unbridled pleasure down Shadow’s spine.  

“Finger yourself.”  

Sonic’s fingers find his hole happily, knowing just where to brush against on the spongey surface to get himself shaking. Shadow’s thrusts become sloppy as the volume of his growls increase, watching in bliss as a particularly hard thrust forces a few fat tears out of Sonic’s closed eyes, adding to the mess on his muzzle.  

“You’re such a good boy, Sonic. You make me feel- hhng... so good. Only you can make me feel this good.”  

That final praise is Sonic’s undoing, a deep moan rumbling through his chest as he tightens around his fingers and cums, mouth full and ready for his prize. Seeing Sonic looking so blissed out is the final puzzle piece needed for Shadow’s own release, a guttural groan escaping as he holds Sonic’s face flush against his pelvis, tongue flat against the underside of his knot and lets his cum pump directly into his throat.  

Blue ears twitch and more tears run down his cheeks but he doesn’t complain, far from it as everything Shadow overwhelms him, swallowing around him like his life depends on it. Shadow takes a moment to savour the warmth one last time, before pulling Sonic’s mouth away. He rests his hands on his ears and rubs them gently to try and clear the fog away from his eyes.   

Sonic simply sits dazed, fingers still in his hole and slumped with his head on Shadow’s thigh, open mouth leaking bits of drool and Shadow onto the black fur. They sit like this for a while as they come down from their high, Shadow’s protective instinct eventually winning against the possessive one and forcing him to lean down and place a kiss between the blue ears.  

Slowly, he pulls Sonic up onto the bed beside him, giving him a once over to assess his state; his eyes look mostly back to normal, expect his pupils are blown huge. Shadow takes the fingers Sonic was using on himself to give them a quick clean with his mouth before starting the rest of his post-sex grooming ritual.   

He lays Sonic stomach down by the pillows, making sure he’s comfortable before resting beside him with an arm around his waist.  

“T-Thank you.”  

“... Did I hurt you?” Shadow asked hesitantly, still feeling very protective at the moment.  

“No, I liked it. I really liked it. I liked all of it.” Sonic mumbled into the pillows.  

At this, Shadow raises a brow.  

“Even the... breed-?”  

“Even that!” Sonic huffs.  

Shadow stores this information away for later, for when he’s back to feeling possessive.  

“Noted.”  

Sonic eyes him with a pout before turning his head into the pillow and mumbling a complaint.  

“Mmm?”  

“Are you gonna keep grooming me or what?”  

Shadow lets out a scoff at the attitude, but moves over to drape himself alone Sonic’s back anyway, propping himself up on one elbow to nose at the other’s shoulder.  

“You’re lucky I’m in a good mood, Faker. Enjoy it while it lasts.”  

“Yeah, yeah put that tongue to good use, won’t you?”  

Shadow nibbles softly at Sonic’s shoulder, pressing small kisses into his fur as they both purr into the sheets. The black hedgehog continues, until he hears the hero’s breathing taper off into slow sleepy sighs. Shadow moves back to the other’s side, resting his arm over a relaxed back and placing his nose by a soft shoulder.  

The urge to protect has him almost frozen in place, his own quills puffing up lightly in defence no matter how much he wills them to go down. Shadow sighs in irritation at his own body, grateful that his cycle was almost over.  

Just one more day.  

However, instead of bringing a sense of peace to his mind like it usually did, something tight settled in his stomach. Normalcy would return in just one more day.  

Naturally, he wrapped himself tighter around Sonic before closing his eyes for the night.  

Chapter Text

Day 7 :  

For the first time in days, Sonic wakes with the sunlight pouring through the gaps in the blinds, blinking away sleep in confusion. Weird. A look over at the clock on the bedside table shows the time to be 9:27am. With a stretch he groans at the feel of his tired body popping, a relaxed sigh leaving him as he simply lies under the heap of blankets and towels on the bed.  

They must have both really needed the sleep.   

Still, it was a little strange. Usually by now Shadow had pounced on him at least two times, insatiable from his cycle.  

Must be nearing the end now...  

A look over to his side and Sonic sees a lump also under the blankets, breathing softly in sleep. Doing his best not to wake the other, Sonic decides to slide out from the bed. Time to make the most of some free time to clean up.  

He heads straight for the bathroom, sighing in relief at the feel of hot, clean water cascading down his back from the shower. No amount of spot cleaning and towels could replace this. He takes his time to use as many scented gels and creams as he can on his abused quills, trying to mold them back into some sort of fashion.  

Sonic leaves the bathroom after this to rummage in the kitchenette, grabbing a bowl of cereal for himself and a handful of snacks to take back for Shadow in case he’s finally able to stomach any food. On his way back he notices his communicator flashing with unread messages on the living room table. He unlocks it to see maybe 10 messages, ranging from worried questions from tails and a few inquisitive remarks from Rouge.  

With a sigh he plops himself down on the couch, flicking through the messages from Tails first. It seems like they had managed to find the final Chaos Emerald and were looking for confirmation for their rendezvous.   

Sonic: 
Hey, sorry for missing the msgs. You know I never check this thing... 

Tails: 
Sonic! Where have you been? We checked out some of the other safehouses, but couldn’t find you.  
Are you OK?? 

Sonic: 
Uh, yeah sorry. Just been getting ready for the rendezvous and taking out those UNITS. There are a lot... 

The last thing they needed was the others barging into the safehouse looking for them.  

Tails: 
We messaged Shadow too. Where is he? It’s not like him to ignore Rouge. 

Sonic: 
Oh, yea, he lost his comms. Sorry!!!  

Tails: 
Sonic... 
You should have told me >.< 

Sonic: 
Yeye, my bad. Listen, I’ll see u in 2 days, right? 

Tails: 
Right! I’ll have Shadow a new comm ready by then too! 

Sonic:  

Great!!! Seeya ^.^  

With a sigh he closed the messages and switched to his chat with Rouge.  

Rouge: 
Hey Blue. Are u and my fav handsome hedgehog getting along?? Not heard from him in a while (╥_╥) 

Rouge: 
ohhh. I see (⸝⸝> ᴗ•⸝⸝) 
Don’t wear him out too much Blue. I need him in top shape!!!! 
 

Sonic simply looks at the messages with his mouth ajar, feeling a blush creep up his neck. Instead of responding he closes the chat and leaves her on read. He sits in silence for a moment before he notices the blink of Shadow’s communicator on the table, too.  

Without thinking he picks it up, not being able to unlock it but still able to see the last two notifications.  

Rouge: 
You better give me ALL the details istg 
You owe me for making me worried!!!! (╯︵╰,) 

With a groan Sonic drops it back onto the table, standing with his snacks in defeat and heading back into the bedroom.  

Great.  

Sonic takes the time to replace some of the towels they’d used previously with clean ones, before going over to the side where Shadow was still sleeping and rubbing his hand through a few of the quills poking out.  

“Hey, Shads. I brought some snacks, I think you outta eat something.” he mumbled, pulling the blanket back a little to try and find the handsome face he’d found himself so fond of recently.  

To the untrained eye, Shadow probably looked pretty peaceful. Eyes closed, small breaths, hands under his chin. However, to Sonic, PHD in “Shadow Expressions and body language”, something was amiss. He leaned in closer to try and figure out what it was; a slight furrow in his brow, the hands under his chin clenched hard with claws threatening to cause injury, quills puffed up in defense.   

Hmm.  

With a gentle hand, Sonic nudged a black shoulder, “Shadow? You awake?”  

Not even a grunt. Which immediately set off alarm bells because 1. Shadow didn’t even need to sleep, and 2. In the few days experience Sonic had sleeping beside Shadow, the latter was always alert at the smallest sound.  

“That tired, huh? Well, it’s time to wake up.” This time, his nudge is not as gentle, the motion causing Shadow’s head to loll on the pillow, limply.  

Huh?  

Using his hands, he turns the hybrid over onto his back, taking in the sickly image. His whole body lax except for his quills, which threatened to poke holes into the bedsheets, mouth ajar in an almost silent grimace, chest rising in tiny, stuttered breaths.  

“Shadow? Are you OK?” Another shove at his arm, hands then coming up to the other’s face and squeezing his cheeks together and shaking his head lightly.  

Nothing.  

With a gasp he lets go, watching as Shadow just drops back down onto the bed. He scrambles out of the bedroom and into the living area, picking up his own comms and opening the chat.  

Sonic: 
I broke him!! I’m sorry I broke him!! 
How do I fix him 

Rouge’s response is almost immediate.  

Rouge: 
Honey what 

Sonic: 
He won’t wake up 
He’s breathing but gaia what if i killed him 
Rouge u have to come here rn 

Rouge: 
Blue 
Calm down 
Explain pls ◉‿◉ 

Sonic: 
OK well im sure u know what’s goin on 
it’s day 5 of his cycle??? 
He was fine yesterday i swear 
He’s just kinda sleeping... a lot? 
Won’t wake up 

Rouge: 
HA! 
HAHAHAHA! 
Oh honey this is fine 
Normal part of the cycle but shame on him for not warning you ᕦ(ò_óˇ)ᕤ 
He’s gonna be out for a while, he’s kinda fighting himself rn probably just gotta let it happen 
 

Sonic: 
So I just leave him alone? 

Rouge: 
Yea take the time to rest up 
Because when he wakes up Blue 
You either stay behind a locked door or stay with him, think about what you want 
But if you’re into that then have fun ⸜(｡˃ ᵕ ˂ )⸝♡ 

Sonic: 
????????? 
What 

Rouge: 
He’s gonna be pretty possessive and rough Blue. Full Black Arms Instincts. 
I don’t even think he’ll be all that coherent 
He’ll probably sleep a lot the day after too 
Look after yourself 

Sonic puts down his communicator, sitting still on the couch for a moment. What does one even do in this situation? He can’t just leave him to fend for himself... The whole thing looks painful to Sonic, and he said he would help. He wants to help. But also, he’s apprehensive. Just how possessive will he be?  

Sonic is pretty certain he can fend for himself against Shadow in most scenarios, that’s no problem. But that aphrodisiac...  

Shadow had said it was to make “breeding” easier, but the thought of being out of sorts when he wasn’t sure Shadow could look after him made him wary. Before, he’d had no complaints, because he knew Shadow still had control.  

It’s fine, I just have to make sure I don’t swallow any of Shadow’s slick. I can do that, right?  

With a sigh, Sonic raises from the couch to go check on the other in the bedroom. He’s still laying exactly where Sonic left him before. The hero runs a soothing hand between the other’s ears, ruffling the red fur softly before pulling back.  

Might as well do some cleaning while he had time.  

So, Sonic headed back to the bathroom, filling a bowl with soapy water and a few washcloths. He returned to the bedroom and placed the bowl on the side. Carefully, he used the washcloths to smooth down over Shadow’s matted fur, knowing that he would hate being in such a messy state.  

He made sure to wash down his chest, running his fingers through the white fur he loved laying on so much, and wiping down around his pouch and flank. After, he managed to change the bed sheets around the dead weight that was The Ultimate Lifeform.   

Sonic did a load of laundry while he stewed with his thoughts, also taking time to clean over the stains they’d left on the couch and absently watch some TV. Every so often he would peak into the bedroom to assess the other’s state, but he laid still under the now clean sheets where he’d been left.  

Once all the chores were done it was nearing 6pm and Sonic was starting to feel antsy. He knew that soon Shadow would be waking, he had to be. Was he going to stay or hide out in his own room?  

He spent a lot of time pacing the room, weighing out the pros and cons of either decision, but ultimately it came down to that weird feeling that had been swirling around in his stomach for the last few days. The feeling that only ever felt resolved when he was laid on the bed with Shadow, with a heavy arm around his waist and a mouth kissing at his nape.  

So, Sonic made his way back into the bedroom, sat on the bed with his head against the headboard and waited. And waited. And waited, until the first signs of life finally shook into the body beside him. A twitch of a brow and a grunt were the only warning Sonic got before the body next to him sat up suddenly with a shock.  

Sonic sat dead still, waiting to see what the other would do first.   

A pained groan left Shadow as his breath came out in heavy pants, his hands moving to grip roughly at his quills, as if fighting off an unwanted thought. The covers were pushed back haphazardly, and Shadow’s eyes began searching the room, finally settling on the hedgehog next to him.   

They both stared at each other for a moment, before Shadow’s upper lip curled into a snarl. Sonic began moving on his own instinct as his quills puffed up in defence, however, inching closer slowly until their noses were almost touching, ears going flat against his head in submission. It was hard to know exactly what Shadow wanted from him without that cloudy brain fog guiding him.  

The snarl stopped at the signs of submission and then a hand was gripping the nape of his neck and pulling him forward to press their lips together. Sonic gasped at the intensity of it, feeling their teeth knock together for a moment before they were opening their mouths. There was no fight for dominance as Shadow’s tongue took control, rubbing where Sonic liked it the best and drawing out a happy grunt from the hero.  

That long tongue was once again working wonders to get Sonic riled up, squeaking in surprise when Shadow’s hands found his thighs, pulling them open and slotting himself in between. His mouth then strayed further down, sharp fangs biting hard   at the soft fur of his neck, likely leaving marks under the blue. Sonic groaned as the rough treatment was followed by the soft swipe of his tongue, before repeating the process.  

Both of Shadow’s hands held his chest, thumbs spread to roll over his pebbled nipples while his tongue remained busy on his neck. Down lower, Sonic could feel the wet head of Shadow’s cock rubbing so enticingly against his own slit, so close to where he needed it. Sonic let out a needy whine which was returned by a warning growl.  

Then the warmth surrounding him was pulling back and away, Sonic blinking up in confusion at the lack of stimulation. The next thing he knows there’s a strong hand on his hip, rolling him over onto his front, hips high and pussy on show to present himself.  

Before a blush could even grace his cheeks, fingers were spreading him apart and the wet tapered head of the dick he loved so much was rubbing across his folds. That was the only warning he got before he pushed in to the hilt, a winded sound escaping Sonic’s lips at the intensity of the first thrust.  

Shadow stilled there, seemingly warming his cock with Sonic’s hole, the blue hedgehog waiting with bated breath for his next move.  

“...Keep going.” he moaned as his tail swished happily.  

Without a word he was pulling out to the tip and pounding back in, immediately setting a rough and fast pace that threatened to be Sonic’s undoing. Every single press of those ridges against his sweet spot had the hero seeing stars, his thighs beginning to shake from the stimulation. Sensing his weakening state, the hands on his waist tighten, pulling him back onto the cock behind him manually.  

Sonic lays limp and lets the other do the work, mouth open and drooling into the clean sheets when the first kiss of Shadow’s cock head meets his cervix, sending a pulse through his clit.  

“Nnng don’t stop, please please please-”  

If anything, the pace increases and Sonic spews out a series of “Thank you” and “yes” in a prayer. Behind him, Shadow pants open mouthed, head tilted back, and eyes closed in pure bliss at the feel of Sonic around him. The swelling of his knot makes a wet noise every time it moves against the hole beneath him, begging for entrance.  

Shadow begins the process of slowing his hips into a hard and deep grind, pushing the knot further and further until it finally pops inside, slipping back out one, two times before it tugs back into the warmth. Shadow continues the slow and deep grinding, his own moans escaping at the feel of Sonic’s walls fluttering around him.  

Sonic lets out a shout when a clawed hand moves around to rub lazy circles over his clit, the two fingers working in sync with his small thrusts. It’s with a mumble of Shadow’s name into the pillows below him that he cums, squeezing tight around the knot currently stuffed inside. Shadow gets out a few more grinds before his hips are stilling, pumping his seed deep with a long-drawn-out moan into the air.  

Sonic lays there, held up only by the hands on his waist, trying to focus on recovery when he feels the hips behind him move. It starts out with the smallest of pulls, before a circular motion is set in place, Shadow’s cock grinding into the other even while locked together. The hero shuts his eyes tightly, fighting against the overstimulation that threatens to overwhelm him.   

He’s never felt so full, usually able to rest for this portion while they wait for Shadow’s knot to deflate. But instead of resting, Shadow is moving forward to drape himself over Sonic’s back, sharp teeth finding purchase on the back of his shoulder and holding him in place.  

Sonic feels the urge to submit wash over him, neck craning to give Shadow more room to nibble at his skin, toes curling into the sheets as his cervix once again becomes acquainted with Shadow’s cock.  

“I cant- Ah! Too soon-” Sonic wails into the pillow, despite his own hips pressing back against the feeling.  

Shadow simply grunts into his neck as Sonic tightens around him again, milking him of his second orgasm into the wet hole. It seems that finally, Shadow is willing to rest, kissing softly over the bite marks he’d just left and licking away the sweat from his fur.  

Once the knot has deflated, Shadow pulls out and Sonic distantly feels their joint effort slipping down the back of his thighs. Sonic looks on in awe at the fact that Shadow is still hard. The black hedgehog wraps a hand around himself, knelt on the bed as he strokes languidly over his length. The wet sound fills the air, and he almost wishes it was his mouth working the shaft.  

Shadow watches him with dark eyes, taking in the state of the blue hedgehog under him; ass up and swaying in the air, shoulder and neck littered with bite marks, pussy leaking his cum. Sonic has no shame as he rolls over onto his back and watches the show in front of him, honoured to be witnessing the Ultimate Lifeform in such a state.  

Shadow’s head tilts back as his hand increases the pace, palm rolling over the head of his cock on every upstroke to smear his slick. Sonic’s mouth waters at the thought of how good he tastes, how much he wants it-  

He shakes the thought from his head, tuning back in to the sight before him.  

The sound of Shadow’s groans are going to be imprinted in Sonic’s head forever, thinking about that deep timbre whenever he’s rubbing himself raw in the comfort of his own bed. As Shadow nears the end, he leans closer, aiming so that his spend splatters across the curve of Sonic’s chest, dirtying the peach fuzz there.  

Gaia that’s so hot  

Two dark fingers play with the mess for a moment, before scooping some up on the tips and moving them towards Sonic’s gaping mouth.  

Taste I want to taste I want to-  

At the last moment, Sonic turns his head, feeling the mess smear across his cheek instead. The sound of a muted growl rings out. A warning.  

“No.” Sonic places the back of his hand over his mouth, “I don’t want it. Not today.”  

Despite his voice wavering, he keeps his eyes on Shadow’s, determined to get his point across. The other blinks at him, as if frozen. A look of something unrecognizable flashes across his features for the faintest moment, before the fingers are pulling away. A scratchy sound makes its way out of Shadow’s mouth, as if fighting himself to speak but failing. Instead, his hand returns to the mess on Sonic’s chest and scoops up some more and for a moment Sonic’s heart sinks.  

Can he even hear me in there?  

“H-Hey, are you listening?”  

What if I can’t get through to him? Maybe I should have left him alone for the last day... maybe-  

Sonic watches as the fingers move with the mess, but instead of coming to his mouth, they move lower to press back inside his hole, letting out a breath he didn’t even realise he was holding. Relief crashes over him like a wave as his whole body relaxes back into the sheets, legs turning to jelly as he gives the reigns back to Shadow.  

Sonic feels his eyes become misty as the feeling of overwhelm takes over, his chest aching with something , leaving him feeling needy and wanting. Wanting to hear Shadow’s voice as he praises Sonic, to feel as he kisses along his neck, to see him almost cross-eyed because of how good Sonic makes him feel. Only Sonic.  

The heavenly feeling of thick fingers rubbing along his insides has his thighs shaking where they rest at Shadow’s sides, his soft moans urging the other to keep going, even as tears spill onto his cheeks from the overstimulation.  

How can something hurt so good?  

Shadow watches with an almost vacant expression as Sonic shakes through another orgasm, the hero’s knees coming up to squeeze at Shadow’s waist. Sonic lays there panting, eyes closed and body heavy as he waits for what’s next. The feel of a thumb rubbing softly over his cheek startles him slightly, blinking to see as Shadow wipes at the tear tracks across his fur clean. They watch each other for a while, as Shadow softly wipes away his tears, Sonic blinking as more fall onto his cheeks.  

That weird something settles heavy on his chest again, wanting nothing more than to kiss Shadow silly. Shadow seems to have started his standard grooming practice, smoothing over Sonic’s neck with his tongue and caring to the bitemarks there. However, this time Sonic knows it won’t last long, the feel of Shadow already rubbing against him gaining his attention.  

Sonic is grateful for the brief respite, but the overstimulation takes longer to clear without that blissful mist fogging his senses. He reaches his hand out to grab the back of Shadow’s neck, searching for his eyes.  

“I only have one more left in me, Shads.” he whispers, hoping that he can get through to him one last time for this.  

The other’s eyes seem to scan his face, but he makes no other indication of having understood. Instead, he moves to a kneeling position and picks up the hero’s thighs to slot them on his hip. Sonic feels the wet press of his cock as it slides between his folds a few times, bumping against his clit, Sonic jolting. This continues for a while, Shadow simply enjoying the wet glide before finally slipping in, a stuttered moan leaving his mouth as his eyes squeeze shut.  

“Sonic.” Comes a gravelly voice, strained from disuse.  

Fingers grab at Sonic’s chin, his eyes opening in surprise to see Shadow watching him intently, an almost fire burning in his crimson eyes.   

“Huh?”  

Without another word he tilts Sonic’s head down so his gaze falls onto his stomach, wondering what he could possibly be hinting at, and then he sees it. His own breath comes to a stop, before an almost guttural groan is punched out of him, squeezing his eyes shut for a moment to compose himself.  

Sonic open them and looks on in awe at the shape of Shadow’s dick that is visible by the bulge in his lower stomach. He knew the other was big, but he hadn’t imagined it would be this obvious, especially because his vision had been too cloudy to notice before.  

“That’s so hot fuck , Shads you’re so deep.” he whines.  

Shadow makes a show of pulling out slowly, only to slot himself back inside, Sonic watching as the bulge moves under his fur. A hand grasping his own brings him out of his new daze, placing his palm down on the bulge, before pressing down slightly. The pressure almost makes Sonic lose it right there, eyes threatening to cross as his vision whites out for a second.  

“Ahn! Shad-”  

Shadow keeps both their hands there while he begins a slow pace of thrusting into Sonic, pressing down hard on every other thrust.  

“Look... Look how full you are...” Shadow punctuates this thought with a hard thrust, “Look how well you take me.” Shadow’s voice sounds almost dreamy, slurred and slow as if in a trance.  

Sonic can’t help but agree, nodding his head frantically as he continues to feel that bulge move.  

“I’ll fill you up every day- hnng! I know you love my knot; I can tell every time you squeeze around it.” Shadow lets out a long moan at his own words, head lolling back almost limp, eyes misty as he imagines the scenario, “You want me to breed you.” It wasn’t a question.  

“I do, it feels so good Shads- fuck I need it.” Sonic feels his eyes rolling into his head at the thought of getting to experience this pleasure every day, “I need you... I need you so bad.”  

It’s as if something snaps in the other, a loud growl sounding through the room as Shadow surges forward, hiking Sonic’s legs tight around his waist as he rests their foreheads together, the two of them panting into each other’s face.  

That feeling in Sonic’s chest is threatening to explode, to completely erase him unless he lets it out. With the lust dulling his senses, he fights himself internally, knowing it’s not a good idea to open his mouth. And yet, as his pleasure begins to mount, he can feel his self-control waning, the words beginning to slip from his mouth as he moans. 

“I don’t want this to end. I mean it- Ah! I-I want to tease you every day, I want to see you after a run o-or a fight.” A particularly hard thrust sees Sonic’s hands coming to grab at the sides of Shadow’s face, holding him in place as he continues to speak the words into his open mouth.  

“I want to spar with you and end the day by kissing you until you’re moaning into my mouth. And I don’t want the last time you’re inside me to be in this s-stupid safehouse!” He almost cries as he feels the swelling of Shadow’s knot begin, “I want you on your couch, in my bed, Gaia against your kitchen table! Somewhere I can smell your scent while you’re taking care of me.”  

Shadow’s only response is a deep purr vibrating through his chest, his thrusts increasing in speed as Sonic holds on for dear life.  

“I don’t want anyone else to see you like this.” He babbles, feeling his eyes getting wet at the mere thought of that happening.  

Shadow moves his forehead from Sonic’s to rest it between his shoulder and neck, teeth biting down hard , likely enough to draw blood. Sonic cries out, moving his arms around the hybrids shoulders to keep him close. Shadow’s own arms wrap tight around Sonic’s torso, holding them both flat together, Sonic almost struggling to take in air as shadow continues to pound into him.  

As his sweet spot begins taking a beating from the head of Shadow’s cock, Sonic has enough mind to feel something wet gushing out of him, punctuated by each slap of Shadow’s hips against him and soaking the sheets below. The release of pressure is so good that Sonic’s eyes roll into the back of his head, complete blackness overtaking his vision as his head lolls limp against the pillow.  

Distantly, he can hear Shadow growling into his neck, pace undeterred even as Sonic’s walls flutter around him, begging for his knot. He doesn’t make him wait long, pushing the swollen base flush against Sonic and locking them together as Shadow chants a mantra of “Mine.”  

The feel of warmth spreading through him rouses the hero enough to pull a loud purr out of his chest, happy and content at being so full of Shadow. The black hedgehog continues to grind minutely into the other, prolonging his own release for as long as possible while his mouth suckles on the bite he’d made to Sonic’s neck.  

Eventually Shadow’s tongue slows to a stop and his breaths become quiet as exhaustion overtakes him, resting his full weight onto sonic as they remain connected. And so Sonic lays there, body still trembling as it comes down from the high he’d just experienced with no one to soothe his fears. Fears that were beginning to cloud his afterglow.  

Why did I say that?  

Because he’d meant it. He knows he’d meant it. Sonic didn’t want to see anyone else getting close to Shadow the way he had. He liked that on top of knowing what face Shadow made when he was angry or happy, he now also knew how his face looked when he was in pure bliss, completely relaxed and vulnerable. Sonic couldn’t even blame the aphrodisiac this time, completely sober on nothing but his own emotions.  

But the fear didn’t stem from that, not really. The heaviness he was feeling on his chest wasn’t just down to the hedgehog currently sleeping on him.  

He’s probably been high off hormones and instinct this entire time. Those things he was saying could just be because of that...  

With a sniff, Sonic brought a shaky hand up to stroke through Shadow’s quills, almost preening when a deep purr rumbled through the other’s chest.   

Whatever.   

If anything, he was hoping that Shadow was so out of sorts right now that he hadn’t heard Sonic ranting in the first place. He could do without the embarrassment.   

And so, with a weary sigh, he closed his eyes and finally decided to bask in the afterglow.  

Day 8 & 9:

When Sonic opened his eyes the next day, the first thought that registered in his head was sore . Every single muscle in his body protested as he moved to roll over, no doubt due to all the times Shadow had bent him to his preferred position.  

For the following day, it was as Rouge had said; Shadow slept the entire day through, which left Sonic to once again do any chores needed around the safe house. He cleaned, cooked enough food to make leftovers just in case Shadow awoke, and he contacted the others about the rendezvous.  

They were to meet at the HQ by noon. Eggman was expected to be there in person, and they could finally send him packing from the island.  

As nightfall hit, Sonic contemplated on whether to return to his own room or not. Shadow was out like a log, only his gentle breathing any indication of life, but the thought of laying in his cold bed alone after the week he’d had was almost unbearable.  

And so, he crawled under the covers next to Shadow and rested his head on the warm chest, nosing into the white fluffy fur with an exhale and let his eyes drift shut.  

The next day, Sonic made sure to wake up early, the clock reading 5:11am. Shadow was still thankfully asleep, yet signs of life had returned to him; no longer laying limp on his back but now turned with his back to the other. Holding his breath, Sonic extracted himself from the bed and made haste for the bathroom. After a quick shower, his shoes were on, and he was out the door in a flash of blue.  

It felt good to run again after being cooped up for so long, and it was difficult to feel anything but pure giddiness at the feel of breaking the sound barrier. He ran for as long as he could before getting tired, not wanting to outdo himself before the rendezvous. Besides, he was still feeling the effects of having his legs spread for six days straight. He swerved through trees and thickets of greenery, only stopping once he came to the edge of the island, meeting the salty sea breeze.  

As he neared the safehouse once more, that strange feeling returned to his chest, halting his steps momentarily outside. He entered to the sound of the shower running, his feet pacing him back and forth in the small living area until he heard the sounds stop, zipping to sit on the couch as nonchalantly as possible as he looks through his comms.  

There’s a pause after the door opens, before he finally hears Shadow’s bare feet pad into the room.  

“Sorry, I overslept.” Came the deep timbre of a voice that’s not seen much use recently.   

“Don’t sweat it. Saved you some food, if you’re hungry.” Sonic tries to sound normal. So normal.  

“Maybe later. We should get going.”  

Sonic nodded, moving to get up and head out, but an almost hesitant hand finding his shoulder brought him to a stop.  

“Sonic. We should talk, later.” As to the point as ever.   

“Right.”  

Right.  

Sonic had never been so glad to see the faces of his friends until this very moment, a watery smile gracing his face as he joins them. As Tails scolds him for not keeping in touch properly during the nine days, Knuckles scrutinizes him, eyes squinting as he takes in the sight of the blue hedgehog.  

Sonic had tried his best to clean himself up, but there was only so much a shower could hide and even though the deep bitemark on his neck wouldn’t be noticeable to most, Knuckles was not most.  

“Don’t tell me you guys were fighting this whole time?” Knuckles tsked, eyeing the fading mark under the blue fur on his neck.  

Sonic’s spine went pin straight, a hand clamping over his neck as he stepped back.  

“Don’t be ridiculous.” Shadow deadpanned, looking almost bored as Knuckles glared back at him.  

“Now, now,” came Rouge’s teasing lilt, “I’m sure they got on just fine, right boys?” an innocent looking smile flashed their way.  

Tails eyed them all wearily, “Right... Well, Shadow I got your new communicator ready.”  

Shadow looked confused as he took the new device, knowing that his own was in fact stuffed inside his quills, but took it silently without another word.  

“Anyway! Eggman? Robots? Let’s go!” Sonic chirped, bouncing on his heels in his eagerness to get moving.  

“We don’t know if Eggman is even here in person, but it’s possible. Whatever we find in here, let’s disable it. We have the Chaos Emeralds, so at least we don’t have to worry about that.” Rouge de-briefed quickly, “There are over six entrances to this place, so let’s split up.”  

“Sounds good, let’s keep in touch over the comms.”  

And that’s how Sonic found himself wandering through the halls of the HQ after squeezing his way through one of the secret doors. He’d stumbled upon a few bots in the halls, but nothing remarkable. If anything, the whole place was suspiciously empty.  

Sonic was trying his best to focus on the task at hand, really, but considering what had happened in the last week he felt it could be allowed for his mind to wander a little bit. It’s not exactly something he could just forget, seeing as his body still ached in the aftermath.  

And then after this I have to talk to Shadow...  

His body felt like a ball of nervous energy. Shadow was probably going to thank him for his help and ask that things go back to how they were before. Yeah. Rivals, that’s what they did best.  

Sonic picked up his speed, racing through the abandoned halls almost erratically, desperate to find something to take his anxieties out on. Distantly he heard through his comms that Tails had bumped into Shadow and Knuckles, no sign of Eggman on their side.  

I’ll find him. Focus! Focus! Foc-  

As sonic took his next step he heard a click and suddenly he was weightless and gravity was failing him, his stomach dropping as the sensation of falling hit him. He’d barely begun to process it before he was hitting the ground, grunting from the impact. His eyes scanned his surroundings quickly, blinking in confusion.  

Nothing.  

Or at least, it looked like nothing.  

He was obviously in a container of some kind, small enough that he couldn’t even stretch out his arms in any direction. The material of the container felt like glass, but he couldn’t see anything through it, no discernible objects from the room outside.  

In a flash he attempted to spin dash against the glass, the motion just rubbing the container but not giving any damage. His fist, his foot, both feet, his head, nothing moved it.  

“Huh,” slowly he tapped into his comms and sat down with a huff, “Guys. Uh, so there’s a problem.”  

Tails’ voice came through immediately, “What happened, Sonic?”  

“I’m stuck... somewhere. No clue where or what I’m actually in. I just know it’s prettyyyy small. Ha... and enclosed. Tight fit.” he tried for a light-hearted laugh, but it came out sounding thin.  

“Hold tight. We’ll get there as soon as possible!”  

So, he waited. And he tried not to think about how cramped he felt in the strange container. Or how his legs were starting to cramp from being bent for so long, or how hunched his back was to fit properly inside the small space.   

He closed his eyes to try and ignore just how much he hated feeling trapped, stuck in one place for too long against his will.   

Breathe. It could be worse, there could be water in here too. It’s not that bad. It’s just very small and dark and I can’t see outside and-  

Sonic wrapped his arms around his knees and rested his head in between, ears twitching restlessly for any outside sounds. Sonic doesn’t even know how long he had spent in the container before something hard seemed to shake it roughly, pushing him against the glass.  

Panicked, he let out a whoa as the banging continued outside, forcing him to move around against his will. Distantly, he could hear the constant buzzing of his communicator, but with his eyes closed and his thoughts scrambled he could barely pick it up.  

There were a few more bangs, before suddenly light was cascading through. Sonic’s eyes flashed open in shock as the glass seemed to explode above him, falling onto his head and showering him. He blinked up into the new light, hands clasped tightly over his ears and a frown wrinkling his brow as a surprised “Huh??” leaves his mouth.  

Above him, bathed in the light and falling glass was an angel, a halo of light framing their face as they peered down at him was a snarl, a fang peeking out and red eyes looking even more crazed than his own.  

Angry! I know that one!  

“ There you are.”  Came the deep voice of his angel, their words much softer than the grasp they suddenly had on his shoulders, hauling him out of the container.  

Sonic stumbled out, gripping tight onto his saviour, still too blinded by the lights around him to focus on anything but their voice. His whole body felt stiff as he held on to strong shoulders, trying to centre himself around them.  

“Sonic. Can you hear me? Are you OK?”  

Hands came up to frame Sonic’s face, squishing his cheeks with how hard they grabbed him, pulling until his forehead made contact with soft fur. Soft, fluffy white fur that Sonic loved so much. He inhaled gratefully, comforted by the familiar scent. The same scent he had fallen asleep to many times now.  

“Shadow?”  

Sonic blinks as he pulls away to gaze at the other, noting his expression is still angry. Vaguely, Sonic feels his ears twitching as he fights with them not to flatten. Shadow must notice anyway, because his expression wavers slightly.  

“Sorry I got stuck. I wasn’t paying attention.” He fights the pout threatening to show up.  

Shadow shakes his head, muttering something under his breath before turning back to Sonic, “Nothing new, then.  Are you OK?”  

“Me? I’m fine! It was only a small, dark and constricting space, easy peasy.” A shaky grin.  

A sigh leaves Shadow, but Sonic notices the small smirk on his lips. He reaches a hand forward, a thumb smoothing over the anxious lines on Sonic’s brow before flicking the tip of an ear, “You’re impossible.”  

He doesn’t fight the flush of embarrassment that washes over him before bouncing back with, “Were you worried about me?” Sonic tries for a smirk, teasing.  

Shadow ignores the comment, turning to leave, “Time to go. Eggman isn’t here.”  

“What?”  

“Probably fled after we took back the final Chaos Emerald. We found some manuscripts. Let’s re-group at the entrance.”  

They found the others waiting already outside, Tails and Knuckles checking in with Sonic as soon as they saw him.  

“Glad you’re OK. Honestly, I’ve never seen Shadow move so fast once we heard you over the comms.” Stated Tails under his breath so the others couldn’t hear.  

“Thought he was gonna bite my head off when I offered to help.” Knuckles muttered, “What’s his problem, anyway?”  

“Uh... he’s been a little under the weather, that’s all.” Sonic smiled, chancing a glance in Shadow’s direction and stopping short when he saw the other already watching over them.  

Rouge’s voice filtering over interrupted them, “We should meet up in Westopolis to discuss our next steps. Let’s get out of here.”  

Shadow was very suddenly by his side, a hand gripping onto his elbow, “I trust you can make your own way back?”  

Rouge and the others blinked at that, “Sure, but why-?”  

The next second, Sonic was blinking green from his vision as he stumbled clumsily on hardwood floor, looking around an unfamiliar room. The nausea of suddenly teleporting hit him like a brick.  

“ Shadow! You know I hate that!” he groans, plopping down onto a black couch nearby with zero grace.  

“Sorry.”  

“Where are we, anyway?”  

“My apartment in Westopolis. I figure we have about 2 days until they arrive. Plenty of time to talk.”  

That jolts Sonic out of his nausea like a bucket of water, urging him to properly take in the space around him. It was a pretty clean and basic looking apartment, hardly even looking lived in except for the books occupying the shelves and tables, as well as the occasional houseplant.  

“Nice place.”  

Shadow hummed, moving to join Sonic on the couch, “About last week...”  

Right. Last week.   

“How are you feeling?” Shadow asks as his eyes scan over Sonic, lingering on his neck.  

“I mean... I’m kinda sore but other than that I’m great. I think it’s you we should be worried about. I literally thought I’d killed you.” he points a finger onto a white chest, jabbing it a few times to get his point across.  

Shadow grimaced, looking away, “Yes, I got some strange messages from Rouge.”  

“Yeah. Because I thought I'd killed you! Seriously, you slept for 24 hours straight.”  

“I’m fine, really. And...” Shadow hesitates, eyes flicking around the room in every possible place but Sonic’s face, “Thank you. For your help.”  

“Like I said. Anytime.”  

Shadow shifts in his seat, seeming to think over his next words carefully before mumbling out a muted, “You’d be willing to help again?”.  

Something akin to anticipation rose in Sonic, he could work with this. He would take whatever he could get.  

“Of course I would.”  

Now, Shadow finally turns to face Sonic, seeking out his eyes, “And you just want this to be a seasonal arrangement?”  

Sonic’s eyes search over the other’s face carefully, looking for something, anything. He swallows the lump in his throat, “Well... sure.” A wobbly smile crosses his face as he tries to ignore that heavy feeling in his chest. The same feeling that had made him ramble all his thoughts out into the air.  

Shadow leans closer, brow raised, “That’s not what I remember you said.” Shadow angles himself so he’s sitting sideways on the couch, fully facing Sonic with one arm resting on the back of the couch.  

Sonic takes a moment to steel himself, feeling the blush moving up from his chest all the way to the tips of his ears as they flatten on his head in embarrassment. There is no way...  

“...What I said?”  

A low chuckle sounds, and Sonic takes note of his expression; lips curled into a smirk as he regards him.   

Happy and pleased.  

Sonic groans, placing his head in his hands, “You heard me??”  

“Mmhm.” That smug voice is punctuated by Shadow slowly moving closer, his hands prying Sonic’s away from his face to look at him properly.  

“I-I don’t remember what I said... so.”  

Shadow’s moves closer again, this time warily, as if not to spook Sonic, until his nose ghosts along Sonics, their mouths so close when he murmurs, “ I remember something mentioned about a couch, a bed, maybe even my kitchen table.” Shadow’s hand comes up to caress the nape of Sonic’s neck, resting their foreheads together, “And what was it again? You don’t want anyone else to see me like that?”  

A sound close to a whimper leaves Sonic at this.  

“You’re pretty possessive, aren’t you, Sonic?”  

Sonic’s breath stutters, “Yes. I am.”  

“Well, so am I.” The hand on the back of Sonic’s neck tightens with his words.  

“So, kiss me already.”  

A chuckle of air leaves Shadow’s nose before he’s bringing their lips together, kissing softly at the peach lips. The kiss differed from their previous ones, Shadow taking his time to feel every touch of Sonic’s lips, smacking together wetly as their tongues entered the mix.   

Sonic doesn’t even try to hide the smile from his face as they kiss, nipping at the other’s lips as he mumbles a series of “I like you” ‘s met with a response of “All mine” ‘s from Shadow, holding onto each other like a lifeline.  

The feeling in his chest vibrates through him in a loud purr, matched by Shadow’s own, and it’s to those sounds that they both lie together on the couch until it’s dark, taking all the time they need to familiarize themselves with each other further.