Archive of Our Own ^beta

Chapter Text

Satoru, alias Mumen Rider, nearly choked on his ramen.

“Come-“ he coughed, shaking his head and staring at the other two heroes sitting at the picnic table. “Come again?”

“A threesome,” Saitama said, like he was discussing the weather. “Well, it would really be both of us with Genos, like I’m sharing him with you. You up for it?”

Satoru blinked, trying to wrap his mind around the concept. He sipped at his ramen to give himself time to think.

“Why me?” He finally asked.

“King’s straight,” Genos said, shrugging. Saitama elbowed him in the side.

“You’re not supposed to say stuff like that!” Saitama huffed, but Satoru raised a hand.

“It’s alright,” he said with an awkward smile. “Coming second behind ‘The Strongest Man on Earth’ is hardly an insult.”

“What does strength have to do with it?” Saitama tilted his head in confusion. “You’re someone we trust and Genos thinks you’re hot.”

Well, that was flattering. Genos was frankly gorgeous, even with his metal body, and Saitama wasn’t that bad looking either. Although...

“Just Genos?” Satoru asked, raising an eyebrow.

“I’m not really into anyone but him right now,” Saitama said with a shrug. The cyborg beside him looked thoroughly pleased. “No offense.”

“None taken,” said Satoru. God help him, he was actually considering it... but he needed to understand what was being asked of him. “So... how exactly do you picture this going?”

“I’m sexually submissive,” Genos began, his face completely stoic. “I enjoy being embarrassed, used and degraded by Sensei. However, the idea of being shared, given over to pleasure someone else at Sensei’s orders is very appealing to me. The way I see it, it would mostly be you and me, with Sensei watching and joining in if he feels so inclined. I would appreciate it if bondage, domination and dirty talk were involved, although other options are up for discussion. Furthermore-“

“Twenty words or less, Genos.” Saitama said, rolling his eyes. Satoru just sat there with his mouth agape, eyes wide behind his goggles.

“I want you to tie me up and fuck me while Sensei watches,” Genos said, succinctly.

Satoru took another long pause to process this. He had quite a bit of experience but he’d never done anything close to this kinky. His workaholic nature drove away partners as quickly as his heroic reputation attracted them, to the point where he’d given up on dating altogether.

Never once, in his past relationships or his recent one-night-stands, had Satoru actually gotten familiar enough with someone to get into the more exotic forms of pleasure. The thought was intimidating and exciting all at once... although he couldn’t really picture the stoic and serious cyborg in a submissive role.

“That sounds...” Satoru licked his lips, eyes flicking between the other two men. “It sounds good, but I’m not sure how good I’d be at the whole domination thing.”

“Don’t worry,” Saitama said, smiling. “That part’s easy.”

He grabbed the cyborg’s chin and turned it to face him, pulling the younger man into a kiss.

No, “kiss” was the wrong word.

Saitama ravaged the cyborg’s mouth, demanding submission with his tongue and his teeth. One hand tangled in blonde hair while the other wrapped around Genos’s waist, pulling the younger man close before drifting down to grab his ass.

Genos melted under the assault, mewling and moaning and scrabbling at his mentor’s shoulders. His eyes fluttered closed even as his body arched up to meet the older man’s, shaking with sudden yearning.

In the space of a few seconds, Saitama had turned the stoic cyborg into a whining, blushing, desperate mess. 

“See?” Said Saitama casually, turning Genos’s face towards Satoru. The cyborg’s golden eyes were half-closed, lips spit-slick and hair disheveled. He looked like he’d just run some kind of sexual marathon. “So, you in?”

“Absolutely.” Satoru’s reservations had dissolved as quickly as the cyborg’s self control. His only wish now was that Saitama wasn’t off the table. Who would’ve thought the bland-faced man could do something so... so...

Let’s just say the cyclist was going to have a hell of a time riding home. 

“Great!” Saitama said with a cheerful smile. “So, there’s just a few things we need to sort out...”

It was utterly surreal, sitting in a park in the abandoned part of City Z, frankly discussing preferences and safewords and such while sipping ramen. Genos barely participated in the conversation, at first, swooning against Saitama’s shoulder looking utterly debauched. When he finally pulled himself together, though, he outlined his own desires with almost clinical efficiency and detail.

Satoru learned all about Genos’s unique physiology... or was it mechanics? Either way, Saitama assured him it would be a completely unique experience. Satoru was convinced that would be the case even without vibrating cyborg man-vaginas, but that didn’t make the idea any less appealing.

“So,” Saitama said as he and Genos rose, the cyborg still a bit shaky around the knees in spite of his outward calm. “Wednesday?”

“Sounds good,” Satoru nodded. He really wanted nothing more than to follow the other two home and join Saitama in taking Genos apart... but the couple had a few things to prepare on their end and it was getting pretty late.

“See you then, Mumen,” Saitama said with a lazy wave.

“Satoru,” The cyclist replied. “It seems silly to use hero names for something like this.”

Saitama nodded and helped Genos off towards their apartment, while Satoru turned his bike towards home, imagination racing faster than the pedals under his feet.

Chapter Text

They’d had to reschedule twice. The first time, Genos had lost both legs to an exploding monster and needed extensive repairs. The second time Satoru had gotten tangled up in a bank robbery turned hostage situation.

But the third time was going to be the charm.

Satoru left very early. He foiled a purse-snatching and a mugging on the way there, but still managed to arrive fifteen minutes before the appointed time.

Satoru parked and locked up his bike (named Justice), before digging into the small satchel he’d brought along. Glasses to replace his goggles, a comb to tame the worst of his helmet-hair. Some of his past lovers had asked him to keep the costume on, but it had never sat right with him. Times like these were among the only ones where he took off his hero identity and all the responsibilities that came with it, letting himself be just plain old Satoru. 

He took the steps two at a time, practically shaking with nervous anticipation. After all the time thinking and imagining, he was finally here. He raised his hand and knocked.

“That you, Satoru?” Saitama’s voice came out, muffled by the wood between them.

“Yes,” Satoru replied. A mix of butterflies and hot desire swirled in his stomach, and he licked his suddenly dry lips.

“Come in,” Saitama said. “Door’s unlocked.”

Satoru opened the door and was immediately met with a wet slapping and the sound of moans. He rushed in, dropping his bag and helmet and barely remembering to close and lock the door behind him.

What he saw took his breath away.

Genos knelt on the futon in the middle of the tiny living room, wearing nothing but a simple harness of crimson rope around his chest and shoulders, binding his arms behind his back. Saitama stood before him, hands gripping his hair and fucking his mouth deep and hard. The older hero was panting, sweat running down his bare chest as he gave Satoru a welcoming smile.

“Hey, you’re early,” Saitama said, as casually as he could while pounding his lover’s throat. “I’m just taking the edge off before we get started.”

The cyclist nodded, eyes wide as he took in the carnal tableau. Saitama was ripped. Who knew that under that shapeless costume lay a body that would make sculptors weep? He wished that the bald hero wasn’t wearing pants, unzipped to let Genos get at his cock. What must his ass look like? His legs?

And as for Genos... metal or not, his body was sculpted and masculine, with a trim waist and broad, firm shoulders. Whoever had built him had payed loving attention to every inch, replicating muscle and sinew, the arch of his spine and the plush curves of his ass.

Satoru was definitely wearing too many clothes. 

He stripped as quickly as he could while still taking the time to fold every article into a neat pile beside the door. Arousal was no excuse to be messy in another man’s home, even if said man was currently turning his boyfriend into a whimpering wreck.

When Satoru finally walked into the room, it was just in time to see Saitama screw up his face and shout the cyborg’s name, spilling down his lover’s throat with a few more fierce thrusts. Once the aftershocks had finished, he pulled out and patted the cyborg’s hair.

“You ok there, Genos?” Saitama asked with surprising gentleness. 

“Y-yes Sensei,” Genos said, slurring the words as though half-intoxicated. There was something soft about him, pliant and yielding, the exact opposite of the Demon Cyborg everyone else knew.

Satoru felt like he had been invited into something private and special, almost sacred. He knew he was just there to help the other two men fulfill a fantasy, but the trust they were showing him sent warmth blooming in his heart anyway. He was getting a taste of something he had given up willingly. Even if Satoru didn’t regret his lifestyle, it was comforting to be invited into someone else’s space like this.

“We’ve left our guest waiting long enough, huh?” Saitama said, looking back up at Satoru. “How do you want him?”

“Uhhhh...” Satoru took a moment to wrap his head around his options before reaching his decision. “His mouth looked good.”

Saitama grinned and zipped up his pants, before grabbing Genos by the ropes around his shoulders. The bald man easily manhandled the heavy cyborg around to face Satoru, a fierce smile on his face that the cyclist would never have expected to see. If someone had told him a month ago that Saitama could be this effortlessly sexy and dominant, he would’ve pulled out the breathalyzer.

They’d already agreed that Saitama would take care of the domination part, directing most of the goings-on, so when the bald hero waved him forward Satoru eagerly obeyed. He stood before Genos as Saitama crouched behind the cyborg, once more taking hold of his hair.

“How rude,” Saitama whispered into Genos’s ear, making the younger man shudder. “You haven’t even greeted our guest.”

“Welcome, sir.” Genos’s voice was soft, his eyes half-lidded. For all that he was the tallest man in the room when they were all standing, he looked so small and cute on his knees like this.

“Thank you, Genos,” Satoru said politely. Saitama had told him of the cyborg’s love for deferential forms of address when submitting, but the reality of hearing it was something else entirely.

“May I...” Genos swallowed, an odd whirring sound coming from somewhere in his chest. “May I suck your cock, sir?”

There was no way Satoru could turn down the request, but he had to do something first.

“Just a moment,” he said, dropping to one knee. The other two looked at him in mild confusion until he cupped Genos’s face between his hands, pulling the young cyborg into a kiss.

Satoru couldn’t do what Saitama had done last time, wouldn’t even try. Instead he licked along Genos’s lips until they opened under his, soft and pliant and just a little too smooth to be flesh and blood. The kiss was gentle and searching, exploring new territory without staking a claim. Genos kissed back, tangling their tongues together until Satoru had to pull back for air.

“Thank you,” Satoru said again before rising to his feet. He half-expected Saitama to look impatient or even jealous, but the bald man only smiled.

“Nice legs, Mumen.” Saitama said, nodding to the cyclist’s toned thighs. There was no more lust in his voice than in that of a man admiring a sunrise, but it still made Satoru blush a little. “Nice cock, too.”

“Thanks,” Satoru said. It was an unexpected compliment from a man, in Satoru’s experience. His dick was pretty short and rather thick, which pleased the ladies but made most of his male partners less than interested. If it was too short to hit a prostate and too thick to handle easily, it just made more sense for Satoru to bottom instead. 

He’d been honest about it in their earlier discussion, but the other two men had told him not to worry. Apparently Genos’s equipment was “one size fits all”, and every inch was a pleasure spot. The thought was obviously exciting, but even better was the look Genos was giving him from right in front of his cock.

Genos leaned in slowly, pressing a kiss to the tip of Satoru’s erection. The cyborg’s eyes were black and gold, sultry and submissive, so eager to please. 

“Now now, Genos,” Saitama purred, “don’t be shy. Give the man what he asked for.”

“Yes, Sensei,” Genos said.

Then he opened his mouth and took Satoru’s cock to the base in one fluid motion.

Satoru gasped and almost grabbed Genos’s hair before remembering his manners. It seemed that these two liked to dive straight into things with very little buildup. Satoru was far more used to slow seduction... if this was one of his normal dates, he’d still be barely halfway to first base.

Still, there was no denying the exquisite slick suction around his cock, pulling him deeper into surprising heat. Somehow he’d have expected the cyborg to feel cold, metallic, but Genos’s mouth was so warm and perfectly crafted that if Satoru had closed his eyes he would have barely been able to tell the difference.

But he didn’t close his eyes. Genos’s face was too erotic, eyes half-lidded and cheeks flushed pink. His lips were stretched obscenely around Satoru, and the cyborg looked like there was nowhere he’d rather be in this moment than here on his knees.

Saitama’s hand was still gripping Genos’s hair, pushing his lover to take Satoru deeper every time. His other hand was on the ropes, holding the cyborg up at just the right angle. It was like the bald hero was a puppeteer, working Satoru and Genos with masterful ease.

Then Saitama tugged on Genos’s hair, pulling the younger man off and stilling the his movements like a dog brought to heel.

“You wanna fuck his mouth?” The bald man asked, as though he was offering Satoru a stick of gum.

Satoru hesitated. He’d never even have considered taking such a liberty before today... it was rude, downright disrespectful, no way for a decent man to treat his partner.

And yet... Genos knelt before him with a look of such intense desire, such need, that Satoru knew it would be far from unwelcome... it would be a disappointment if he didn’t do it, didn’t sink his cock into that soft, warm mouth and use it however he wanted.

“Ok,” Satoru said, putting his hands on either side of Genos’s head and gently guiding it forward. The young cyborg opened his mouth and closed his eyes, utterly pliant as Satoru slid inside, inch by inch.

The first thrust was gentle, experimental, but Genos still groaned. His jaw fell slack and the whirring noise grew louder, like the fans of an overheating laptop... was that why the cyborg never seemed to need to breathe?

Satoru kept going, gentle rolls of his hips. Never too hard, never too deep. Even though he was physically incapable of hurting the sturdy cyborg, even though he’d seen that mouth taking Saitama’s much longer cock with no problems at all... taking it so deep and so hard...

Alright, maybe he could do a little more. 

Satoru took a firmer hold on the cyborg’s head, daring to thread his fingers in that soft, blonde hair, then thrust in a little harder. Genos groaned, leaning forward to pull against Satoru’s grip, get a little more cock in his mouth.

“That’s it...” Saitama murmured, reaching his free hand up to rest around Genos’s throat and squeezing, just a little. The cyborg shuddered at the threat, the promise that Saitama could so easily choke him, and Satoru heard the faint sound of dripping. “Go as hard as you want. He likes it rough.”

... well then. Far be it from Satoru to deny the cyborg what he wanted.

The cyclist took a firm hold on Genos’s hair and snapped his hips forward. The younger man moaned, a sound of such rapture, such pornographic bliss that Satoru had no more reservations. 

He started thrusting in earnest, pounding the cyborg’s mouth like he had seen Saitama do just minutes earlier, and Genos reveled in every second of it. Every time Satoru sank into that perfect wet heat was met with sounds of pleasure. The only way it could’ve been better was if Genos’s mouth and the little bit of throat Satoru could reach had vibrated with the noises Genos was making, but his vocalizations seemed to come from some kind of internal speakers rather than air passing over lips and tongue.

Satoru was starting to feel that tension knot up in his belly when he remembered why he was there. The brunette quickly pulled back, panting and trying to collect himself. As wonderful as Genos’s mouth was, he’d promised the submissive youth a good, hard fucking, and he always kept his promises.

“Sorry,” Satoru said, panting for breath. “I was going to come.”

“He does that,” Saitama said, nodding as he pulled Genos back with the hand on his throat. “How are you doing there, Genos?”

The younger man nuzzled into his lover’s shoulder, completely lost for words except for a low, pleased hum. 

“What color are the lights?” Saitama insisted gently, patting Genos’s flank.

“Green...” the cyborg murmured. It was another thing they’d explained to Satoru during the planning session, a code system based on traffic lights. Green was “go”, red was “stop immediately” and yellow was “slow down”.

“Good boy,” Saitama said, pulling Genos into a soft kiss. Satoru felt once again that he was being shown something private and cherished, something nobody else had ever been permitted to see. It was almost more overwhelming than the feeling of sinking into the cyborg’s mouth.

Satoru turned aside to the bottles of water on the desk, grabbing one for himself and taking a long swig. He needed to calm down, get his raging erection under control. The night still lay before them all, and the best part was yet to come.

Chapter Text

After a few long swings of water and some deep breaths, Satoru finally felt his self control come back. At least he no longer felt like he was going to come at the slightest touch and disappoint his hosts. 

Speaking of his hosts, Saitama was gentling his lover with soft kisses and praise, letting the cyborg lean against his bare, muscled chest. Once again Satoru regretted that the bald hero was off the table... he’d bet that Saitama’s cock would feel amazing in his ass.

Still, that wasn’t was Satoru was here for, and seeing the flushed and pliant cyborg in front of him, so ready and eager to be fucked, sent hot lust searing through the cyclist’s body. 

Satoru finished off his bottle of water and grabbed another, handing it over to the bald man who took it with a nod. The brunette wasn’t sure if the cyborg needed water, but in Satoru’s experience hydration was always a good idea when it came to sex. 

Sure enough, Saitama gave Genos a few sips from the bottle before finishing the rest himself.

“You ready to keep going?” Saitama asked, mildly.

“I think so,” Satoru replied with a nod, and Saitama grinned.

“Spread your legs, boy,” the bald man murmured into his lover’s ear, who obeyed with a whimper as Saitama helped. Soon, Genos was leaning back against the older man who was holding him by the thighs, tilted up and back to give Satoru the most obscene view.

While Genos’s mouth was almost completely human, his “vagina” was far more like what Satoru had expected, mechanical and strange. It was a long, arched ridge from his hips up along the cyborg’s belly, clearly an addition to his normal design. The bottom was already dripping with clear slick, running down his legs and ass, coming out of an intriguing little pink opening.

Satoru got to his knees and inched closer. They’d asked him about his favorite lube flavors the other night, and sure enough the scent of strawberries floated up from between Genos’s spread, trembling thighs.

“May I lick you?” Satoru asked, and Saitama shrugged. 

“If you want,” the bald man said, “but it’s not really easy to get in there, and he doesn’t feel much on the outside.”

Satoru nodded, mildly disappointed. It was odd, the way Saitama did most of the talking, almost as though Genos was an object for them to use... but maybe that was the point? The cyborg seemed to thrive on being used, being treated more like a sex toy than a person. Satoru directed his next question towards the bald man.

“Can I finger him, then?” Satoru asked, and Saitama gave him an approving smile. 

“Sure, go right ahead.” The bald man lifted his lover higher, granting Satoru easier access while the cyborg gave a wanton moan.

Satoru leaned forward to press a kiss against Genos’s lips. The younger man parted his mouth easily, so eager to please... then whimpered as the cyclist pressed two fingers inside. 

Oh. Oh.

Satoru had been prepared for slickness, for heat, but the way Genos twitched around him? The bumps and ridges and little changes in texture? It was like nothing he’d ever experienced before. The young man’s pussy literally vibrated around his fingers, with clever little motors spinning and squeezing and massaging. The diabolical device was clearly designed to drive any man who used it completely mad.

“Holy...” Satoru never swore as a rule. Mumen Rider had to be a good role model... but if ever there was a time for inappropriate language, this was it. “Holy fuck.”

“I know, right?” Saitama said, with a proprietary smile. “His cunt is the best.”

“No kidding...” Satoru murmured. He moved his fingers in and out, making the cyborg whine and writhe and clench around him.

“Think you can handle it?” Saitama asked with mild concern. “I had to have him turn the motors off the first time...”

“No, I’m good.” Satoru shook his head. He had good sexual stamina when he put his mind to it, and this was his only chance to experience being inside Genos... unless the other two ever invited him back.

Fuck, if that was even a possibility, Satoru was determined to give the best performance of his life.

Satoru moved in closer, kissing Genos with searing intensity while fingerbanging the younger man mercilessly. The cyborg groaned and writhed, crying out as Satoru sucked on his tongue and delved into his mouth.

“That’s right...” Saitama said, inches from Satoru, before turning to nibble on the blonde man’s ear, playing with the earring in a way that made Genos come even more undone.

By the time Satoru’s fingers started to tire, Genos was fucking himself down on them as much as he could while Saitama held him up. Satoru pulled back and surveyed the cyborg’s blissed-out face and nodded. If anyone looked ready to be fucked, it was the panting, dripping, desperate mess before him.

“How do you want him?” Saitama asked. 

Satoru pressed his slick hand to his lips, savoring the taste of strawberry as he sized up the situation. Genos was too heavy for Satoru to easily hold up or move around, which eliminated many positions. Perhaps if Genos got on his hands and knees... but that would mean Satoru couldn’t see his face.

“I...” Genos’s voice surprised both of the other men. It was soft and dreamy, like Genos was in some kind of trance. “Please... can Sensei hold me? I want... I want you to do it... while I’m touching Sensei...”

The two older men locked eyes and nodded. It seemed right, somehow, that Genos would give himself to Satoru while still clearly belonging to his master.

Saitama hitched Genos higher, folding the blonde man nearly in half so that his hole was at just the right height and angle. Satoru marveled at the other man’s strength, able to lift and move his cyborg lover’s body without even the slightest effort.

Satoru lined himself up with that inviting little opening, but paused when Saitama shook his head a little.

“Genos...” he whispered in the younger man’s ear. “Do you want it?”

“Yeeeeesssssss..!” The world came out in a long, low moan.

“Beg for it,” Saitama said.

“Please,” Genos babbled, eyes squeezed shut and legs shaking in his lover’s grip. “Please, please please Sensei, please let me have his cock... I want it, I want to be good for you...”

“Ask Satoru. Beg for him to fuck you.”

“Please!” The word was between a sob and a scream, utterly broken and needy. “Please... please give me your cock sir! Please fill me up, come inside me... use me, take me, please please fuck me!”

“What do you think?” Saitama asked, raising an eyebrow at Satoru. “Good enough?”

Honestly, Satoru was almost as desperate as Genos at this point, but he knew that this was all part of the game, the fantasy, the way these two pushed and pulled and pleasured each other.

“I think...” Satoru said, fighting to sound casual. “I think he makes a good point.”

“Right,” Saitama nodded at Satoru, “He’s all yours.”

Satoru braced one hand on Genos’s shoulder while he lined up his cock with the other... and the next moment he was sliding into wet, tight heat. 

Genos moaned deeply as Satoru thrust inside, and the cyclist couldn’t help but echo him. It felt fantastic. All the twitching and squeezing and vibrating and massaging... it was the ultimate sex toy, tailor-made for pleasure. 

“You like that?” Saitama whispered in his lover’s ear, “you like having another man inside you? Being a good toy I can share?”

“I...” Genos’s voice was slurred, like he was drunk on pleasure. “I love it... I love you, Sensei...”

Satoru’s eyes widened. Genos had literally declared his love for Saitama while Satoru was balls-deep inside him... in any other circumstances, that would’ve been painful, heartbreaking, enough to make the cyclist stop and leave and never look back... but now? As he watched Saitama press a kiss to his cyborg lover’s lips, Satoru felt nothing but happiness for the other two men.

He put his hands on Genos’s hips, digging his fingers into the supple black material hard enough to leave bruises on any other man. The leverage let him thrust deeper, faster, dark hair falling into his eyes and glasses nearly fogging up from the sheer heat of their coupling. 

Genos writhed, mouth open in a never-ending stream of moans and half-formed pleas, so desperate and wanton it took the cyclist’s breath away. Even with his metal bulk the cyborg still jerked a little with the force of every thrust, the strength Satoru put into it by sheer force of will.

Saitama held Genos steady, as solid and immovable as bedrock. His normally impassive face had a look of dark hunger, a passion that shook Satoru to the core.

“How is it?” Saitama asked, eyes fierce in a way that would normally be frightening. Satoru was lucky there was no jealousy there, only desire... but not directed at the cyclist. “How’s his pussy feel?”

“It’s the best,” Satoru said, and that wasn’t hyperbole. Every thrust was met by hot, slick tightness, the gripping, massaging motors that made it hard to keep his head straight. He was determined to make Genos come first, like any decent man, but it was going to be a near thing.

“Good” Saitama said, then turned his head and growled into his lover’s ear, “When he’s done with you, it’s my turn. I’m going to fuck you with his cum still inside you.”

“Fuck,” Satoru gasped. It was probably the hottest thing he’d ever heard. Genos wailed and tried to thrust himself down on Satoru’s cock, utterly and completely undone... but Saitama held him firm. Genos was just here to be used, filled and fucked at his master’s will, and he clearly loved every second of it.

“Turn it up...” Saitama said, voice rough and pupils blown. “150, no, 200% sensitivity. Come on his cock for me.”

Genos obviously obeyed the order, as his moans and whimpers turned to screams of pure pleasure. The cyborg jerked and spasmed in his lover’s grip, toes curling and thighs shaking. He clenched hard around Satoru’s cock as his back arched into a beautiful, trembling bow. 

It was all too much for Satoru. His hands shook on the cyborg’s hips and his thrusts faltered.

“I’m-“ Satoru gasped, “I’m going to-“

“Come.” Saitama’s voice was all firm command, hard and undeniable. “Fill him up.”

Satoru obeyed, burying himself deep inside Genos with a hoarse cry. He came so hard he nearly blacked out, painting the cyborg’s insides with his come.

The cyclist pulled out quickly, as Genos’s motors were still going, then sagged against the cyborg’s heaving chest. Saitama’s eyes were still fierce and hungry, but he let the other two men bask in the afterglow for a moment.

“Are we green?” He asked, voice rough with desire.

“Green...” Genos murmured, almost too low to hear. Satoru gave a weak thumbs up, then scrambled away as well as he could on shaking limbs. He knew what Saitama wanted to do next, and he couldn’t wait to see it.

Chapter Text

Saitama lowered Genos gently to the futon, manhandling the cyborg so he was on his knees, ass in the air. The young man’s arms were still bound behind his back, so his chest and cheek rested on the floor. The bald man had made certain to arrange Genos so his face was pointed straight towards Satoru.

Satoru blushed hard at the look on Genos’s face. The cyborg’s eyes were rolled back in his head, lips slack and shining with the spit from uncounted kisses, hair a total mess. He’d obviously just been fucked within an inch of his life... and they weren’t even close to done.

“90% sensitivity,” Saitama ordered, kneeling behind Genos with a predatory expression and unzipping his fly. “I want you to feel it.”

“Y-yes, Sensei...” Genos said, licking his lips in a kind of exhausted anticipation. “Please, use me as you like...”

“Always,” Saitama said, grabbing Genos’s hip and lining himself up.

As usual, Saitama didn’t start slow. He slammed into Genos, taking what was his with no hesitation. Every thrust was a claim, a mark of ownership... even if Satoru’s come was still inside the cyborg, there was no doubt who Genos belonged to.

“Sensei... Sensei...” Genos panted out the word like a mantra. “So good, so deep!”

“That’s right,” Saitama said, giving the cyborg a proprietary smack on the ass. “You’re mine.”

“Always...” Genos was panting, moving his hips as though trying to take Saitama deeper with every thrust. “Always yours...”

The sight was impossible to look away from, hotter than any porn Satoru had ever watched. The two men moved like a well-oiled machine, perfectly in synch with one another. How long had they been doing this, to develop that kind of rapport? How many times had Saitama tied his lover up, bent him over and filled him up with cock?

“Hey, Satoru,” Saitama said with a feral grin at the brunette. “Your cum feels great inside him.”

“T-thanks,” Satoru said, eyes wide. He wondered what it might be like, sinking into Genos again after Saitama was done... tag-teaming the cyborg all night long. His flaccid cock gave an interested little twitch, and Satoru bit his lip. 

Saitama gave a thoughtful little hum, before seizing the ropes around Genos’s shoulders and pulling the cyborg so he knelt upright, back flush against Saitama’s chest. All this time, the fierce, pounding rhythm had never stopped, never slowed. Even as the angle changed and the penetration grew much shallower, the bald man kept going. 

A hand snaked around Genos’s neck, squeezing just a little as Saitama growled into the younger man’s ear.

“See the way he’s looking at you? I bet he wants to fuck you again...” Saitama chuckled a little. “I don’t blame him, who wouldn’t want a go at you, seeing you like this?”

Genos whined in a way that went straight to Satoru’s cock. He wholeheartedly agreed with the bald hero’s sentiments.

“Wish your pussy could stretch a little more...” Saitama mused, even as he kept up his relentless, almost brutal thrusts. “You’d probably like it if we were both inside you...”

Genos nodded, too breathless to speak, to make any sounds but low, needy moans. 

“I have an idea...” Satoru said. He was starting to get the hang of this, think up his own dirty plans. “What if we take him at both ends?”

“Brilliant,” Saitama said, grinding his cock into Genos one last time, before pressing his lips to the younger man’s ear. “Green?”

“Green!” Genos whined. “Green, green, green!”

Saitama grinned and motioned Satoru into position, kneeling with his legs spread. His cock was more than halfway hard by now, too aroused to wait out his normal recovery period.

Saitama did something with the ropes behind the cyborg’s back, releasing the younger man’s arms but keeping the rest of the harness in place. Slowly, Genos was lowered until he knelt on hands and knees, face level with Satoru’s cock.

“May I suck you again, sir?” Genos asked, and Satoru grinned down at him, taking two big handfuls of hair.

“Better than that,” Satoru said, trying his own version of Saitama’s dominant voice. “I’m... I’m going to blow my load... right down your pretty throat.”

The words sounded like something out of a cheesy porno, but it didn’t matter. Genos whined, the fans in his chest whirring louder and louder. Saitama was grinning.

“See?” The bald man said. “Told you it was easy.”

Satoru had to agree. Genos opened his mouth and took the cyclist’s cock like he’d been born for it, like nothing would make him happier than pleasing the other two men. The urge to dominate him, to wring more of those noises out of him, was overwhelming.

This time, Satoru didn’t hold back. He thrust in hard and deep, brushing against the back of Genos’s throat and forcing the cyborg’s lips down to the base. The younger man let out a contented little sigh, eyes drifting closed as he basked in the feeling.

Then Saitama started moving again.

The first thrust coincided with one of Satoru’s, abruptly filling the cyborg at both ends. Genos cried out in pleasure and surprise, then again and again as the two older men set up a rhythm inside him. Both would pull out at the same time before plunging back in, driving the cyborg wild with their synchronized movements.

“He looks... so good...” Saidama breathed, his usual cool crumbling by the second, “filled up like this.”

“Perfect,” Satoru agreed.

“Such a good little slut for me, for us...” The bald man said, making Genos let out a desperate whine.

“Yeah...” Satoru had never said anything like that before, but did his best to join in. “Good boy... you.. you take it so well.”

Genos practically glowed at the praise, letting out a sweet little cry around his mouthful of cock. The air was thick with the smell of strawberry lube, running down Genos’s thighs along with tiny rivulets of Satoru’s cum.

Saitama dug his fingers into Genos’s hips, thrusting in deeper and harder than before, making the cyborg wail even as Satoru tried to match the other man’s pace. The whole thing was building to a crescendo, all three men nearing their peak.

“Turn it up,” Saitama growled, “as high as you can stand. Come!”

Genos’s whole body snapped taught, artificial muscles straining at the sudden rush of pleasure. He jerked under the other two men, all half-muffled cries and desperate passion. Black tears welled at the corners of his eyes as the young man came and came and came.

His orgasm sent off a chain reaction, pulling Saitama along with a shout and a few last, powerful thrusts. The look of bliss on Saitama’s flushed and sweaty face, the felling of Genos’s slack mouth shaking around him... it was too much for Satoru. The brunette hunched over Genos, forcing the cyborg to take it all, every inch and every drop, until Satoru was completely drained.

The three men tumbled into the stained and soaked futon in a sweaty heap, limbs tangling together as they panted for breath. Even Saitama was breathing hard, his inhuman power brought low by something as simple as sex. Genos’s fans were whirring like they were going to break, as another trickle of white cum dripped out of his hole.

“Mmmmmmmm...” Saitama hummed in pleasure, pulling his lover into a soft kiss. “Four loads in one night... such a good boy.”

Genos was making a noise that sounded suspiciously like purring, nuzzling into the older man’s grip like he never wanted to leave it.

Satoru fidgeted, suddenly feeling out of place. His part in the whole thing was done, right?

“I should...” Satoru panted, “I should get going.”

He didn’t want to leave, but he knew his place in this whole situation. There were boundaries he didn’t want to overstep, after all.

Saitama frowned at him, even as he kept petting Genos’s hair.

“Do you want to leave?” Saitama asked. “You’re cycling home, right? How can you do that if your legs are shaking?”

“Uhhh...” to be honest, Satoru wasn’t sure if he could ride home without crashing into something. Even at 25, two orgasms in one night after a day of hero work had definitely taken it out of him.

“Come on,” Saitama said, getting to his feet and picking up the half-conscious cyborg like he weighed nothing. “You helped make this mess, let’s clean it up.”

The bathroom was small, but they all managed to fit inside somehow. Saitama took care of washing the cum and lube off of Genos’s body, showering him with kisses and soft praise, while Satoru was given the vaginal attachment and an instruction manual. The device was surprisingly easy to clean (and thankfully waterproof). By the time they were all wiped down, Satoru was barely awake enough to help pull out the spare futon.

He was, however, awake enough to be disappointed that Saitama had changed into pajama pants while the other two slept naked. 

It was a tight squeeze, three men on one futon, but Genos turned out to be an insatiable cuddler, perfectly happy to use Saitama as a mattress. The white noise of the cyborg’s fans and humming core was soothing, and it wasn’t long before Satoru drifted off to sleep.

Chapter Text

Satoru slept the same way he always did after a good workout: deep and dreamless... even more without his usual morning alarm.

By the time he actually woke up, the sun was shining through gaps in the curtains, and he could hear low murmuring in the kitchen, the clinking of utensils and the hissing sizzle of a frying pan.

Saitama saw him sit up and gave a friendly nod through the little window between rooms. “Morning, Mumen. Bathroom’s free.”

Satoru thanked him and went to freshen up, glad he’d brought some toiletries just in case. By the time he’d finished in the bathroom and changed back into his uniform (with clean underwear), he was properly awake.

His hosts greeted him with rice, natto and a fried omelette: simple, cheap ingredients prepared well. There was even some instant coffee... not his preferred brand, but a kind gesture from two tea-drinkers.

They chatted idly as they ate... hero work and recipes, movies and manga. Genos reached over at one point to pluck a grain of rice from the corner of Saitama’s mouth with a soft smile. At home, the two lovers had an easy, familiar closeness, as comfortable as a well-worn pair of shoes.

“Hey, Satoru,” Saitama asked after polishing off his bowl, “you wanna do this again?”

The cyclist had been hoping that question would come up, but he held himself back from immediate agreement.

“I’d like to...” he said, carefully, “but I’m no good in relationships. Would it be alright if there’s no strings attached?”

“No strings,” Genos said, firmly. He reached his hand down to twine his fingers with Saitama. “I’m only in love with Sensei.”

“Just friends with benefits.” Saitama confirmed.

“Then it’s settled,” Satoru said with a soft smile. 

He was still smiling when he strapped on his helmet and straddled his bike, riding off on his morning patrol of City Z. All in all, things were looking pretty good.