Archive of Our Own ^beta

Chapter Text

Katsuki woke up slowly. His head throbbed, a nagging pain reverberating across his temples and behind his eyeballs, his eyes bleary and crusted almost shut. His face felt dry and damp at the same time: lips chapped and nose sore, skin itchy with sweat and — gross — a bit of snot. He rolled onto his side with a snort and blindly smacked his hand around on the bedside table to secure a tissue. With a wheeze, he hauled himself upright and began the painful process of mopping himself up.

Useless immune system.

He was a hero, damn it. It was pretty fucking unheroic to be incapacitated by a common cold. Pedestrian; even mundane. But his agency had strict rules about illness. Anyone contagious was barred from coming in: too much risk of infecting other heroes or the public. Katsuki was under strict instruction to stay home until it cleared up.

Resting. In bed. Doing nothing.

Fuck.

Steeling himself, he hauled himself out of bed and dragged his limbs to the bathroom where he had to lean against the wall to take a piss. Just standing upright was enough to make him dizzy, and the thumping in his head only intensified when he hobbled to the sink to wash his hands.

As he splashed water on his face, he couldn’t help catching a glimpse of himself in the mirror. It was undeniable: he looked rough. Dark hollows lurked under his eyes, his sallow complexion glistened with the sheen of fever, and the skin under his nose was red and peeling.

Ugh.

With a wordless grumble, he yanked the cabinet open and fumbled for the lotion. He gritted his teeth through the sting, applying a generous layer all over his face before risking another glance at his reflection.

Better. Maybe. Still fucking disgusting, though. Katsuki slammed the cabinet shut and heaved himself back to bed with a groan, dropping onto the mattress hard enough to bounce.

Not being able to work was bad enough, but he couldn’t do anything like this. He’d tried to read, but it made his headache flare. He wouldn’t compromise on screens in the bedroom, so watching TV was out. Maybe he could move to the couch? But the prospect — dragging himself there, building a nest of blankets, finding the remote control from wherever Deku left it after his last hero documentary marathon — was too much. Not worth it.

With huge effort, Katsuki rolled himself to tug a corner of the blanket around his middle before collapsing back into the sheets. They felt sticky, clinging to his bare arms and legs to leave him oddly aware of his own skin: somehow too hot and too cold at the same time. Every part of his body was prickly and sensitive, and no matter how much he squirmed he couldn’t get comfortable.

So sleeping was out, too. His whole body had betrayed him.

It was some combination of frustration and boredom that had him reaching down, palming half-heartedly at himself through his sweatpants. His dick stirred, slightly. A trace of pleasure made it to his brain through layers of fatigue and aches. Another experimental rub and he started to harden, gradually, coaxed to life by his insistent fingers and force of will.

Well. Nothing better to do.

Katsuki settled on his side, knees loosely bent, blankets around his waist leaving his arms and legs free. One hand burrowed below his waistband to stroke himself directly, skin on skin, pulling long slow tugs up and down the shaft and working himself to full hardness.

It felt… alright. Nice, even. The touches were lazy, unhurried, not enough to get anywhere but serving as a distraction. It was a relief to feel something other than discomfort for once, the lazy simmer of arousal drawing his mind away from his aching body and into a liminal space where he could float in a semi-pleasant haze.

And then the door opened, and Katsuki’s bubble popped.

He whipped his hand out of his pants like he’d been burned. “LEARN TO KNOCK, DIPSHIT!” he roared — and fell into a violent coughing fit.

“Kacchan! Ah, I’m so sorry!”

Fucking Deku — because of course — flapped around in the doorway, waving his hands in front of his bright red face. By the time Katsuki wrestled his breathing back under control, Deku had settled with his fingers slapped over his eyes.

“I wanted to ask if you needed anything!” he said loudly into his palms. “I was about to start dinner, so I was wondering if you wanted me to make soup? Maybe fetch a glass of water, or a blanket, or…”

Deku’s voice trailed off, abandoning his sentence to dangle unfinished in the air. Slowly, he let his hands lower, just far enough that he could peek over his fingertips.

Katsuki scowled back at him. He didn’t say anything, but he made an unpleasant snorting sound. Just to be an asshole.

“Um. Kacchan.” Deku wavered back and forth on his feet. “I did… see that right, didn’t I? Just now. You were… touching yourself?”

Katsuki’s face flared with heat, but he burrowed deeper into the blankets to conceal it. “What the fuck else am I supposed to do?” he grumbled — then had to pause to cough up even more mucus. “Ugh. This is shit, I feel like shit — I got bored, okay? Jerking off passes the time. Why are you judging me, anyway?”

Deku shook his head frantically. His arms had dropped to his sides, revealing a crimson flush over his cheeks that probably rivalled Katsuki’s.

“I’m not judging you!” he said in a rush. He took a few steps forwards, all at once, before coming to an abrupt stop again. His expression was hesitant, but his gaze stayed intense on Katsuki’s face. “I’m really, really not judging, I promise it’s not that. I’m. Uh.”

Katsuki groaned. “What, nerd? Spit it out or leave me alone, I’m too sick to put up with this shit—”

“Can I help?”

As soon as the question was out of Deku’s mouth, his eyes went wide. He bit his lip, as if to take the words back — but unfortunately for them both, there was no unringing that bell.

“Deku.” Katsuki’s voice was flat. “What?”

Deku finally looked away at that point, but he took another few steps towards the bed. His forefingers tapped together — but his brow was set in a subtle frown, like he expected a fight and wasn’t about to back off. “I — I just thought — we’re partners, aren’t we? Why should you do this on your own? I can do it, if you need me to — if you want me to — it’s fine! I’m, um, I’m happy to.”

“Deku, I’m fucking gross,” Katsuki began— 

And was immediately vindicated when another bout of coughing burst from his lungs. He curled over himself, hacking and spluttering at the congestion in his chest, until he’d finally managed to clear it. 

“See?” he rasped, still catching his breath. His eyes were streaming; he groped around the bedside table for a clean tissue. “I’m a snot factory, don’t be stupid.”

“I don’t mind!” Deku pressed a tissue into Katsuki’s fingers, and followed up by clasping his clammy hand. “Kacchan,” he said, holding tender eye contact. “I’m here for you. We’re in this together. You’re never gross to me — whenever you want me, I’ll be there.”

Katsuki blinked at him through watery eyes, startled into silence.

Deku seemed to take that as his answer. Before Katsuki could finish wiping snot from his face, Deku had climbed into bed with him, unwinding the covers from Katsuki’s waist and settling at his back.

Katsuki could feel the fever on his skin when Deku wrapped his limbs around him, cold sweat lingering on his t-shirt and making the fabric cling. Unperturbed, Deku wound an arm under Katsuki’s neck and around, cradling his head in the crook of his elbow and raising his hand to stroke the hair from Katsuki’s damp forehead. The fingers of Deku’s other hand splayed on Katsuki’s stomach, petting gently.

“Izuku,” Katsuki croaked again, gripping weakly at Deku’s wrist. “I’m serious, you don’t gotta do this.”

“I know that, Kacchan.” Deku nuzzled his forehead into the back of his neck. “But I want to, okay?”

Katsuki was so stunned he barely reacted when Deku slipped a hand down his pants.

No surprise, his dick had long gone soft. But Deku’s hand was an old and trusted friend. It didn’t take long for Katsuki’s cock to take interest again, roused by the familiar sensations. The way Deku closed his fingers around the length, tugging slightly too rough in a way that made Katsuki’s toes curl; the bumpy texture of scarred skin and damaged knuckles. Soon Katsuki was fully hard and throbbing, pulse beating fast in the grip of Deku’s fist.

Deku hummed, pleased, into the nape of his neck. His strokes got firmer, more deliberate, thumb toying with the head on every upstroke. Katsuki groaned, his hold tightening around Deku’s wrist — but all that got him was a front row seat to the way Deku’s forearm worked, the muscles and tendons flexing as he pumped his hand.

“Feeling good?” Deku whispered.

His mouth had migrated upwards, now peppering kisses across the slopes of Katsuki’s shoulders, along his neck, the curve of his jaw. Katsuki attempted a huff, and barely managed to avoid making a mess on the pillow. Instead he growled, turning to hide as much of his face as he could.

“You’re gonna get sick,” he mumbled.

“I don’t care,” Deku said immediately. His voice sounded tight, taut in his throat, hot breath puffing over Katsuki’s sweaty skin as he continued smothering him with kisses. “You’re so sexy, Kacchan — you know I can’t resist you.”

Sexy?

The nerd was out of his goddamn mind. Katsuki had seen himself; knew that he looked like actual, steaming shit. His hair hadn’t been washed in three days. A good half of his face was red and crusty, the rest a mess of clammy skin spotted with flush. Even now, his nose kept running uncontrollably, making him battle to stem the flow with loud sniffs.

And none of that was enough to put Deku off?

Clearly not. He kept up the attention, stroking diligently at Katsuki’s cock and mumbling a stream of encouragement and praise into his ear. Talking him up like he was a god among men instead of a festering petri dish. He was even — Katsuki paused. Reached back with one hand to fumble in the sheets, only for Deku to whine, burying his face into Katsuki’s neck.

Yes, Deku was hard: not only willing to do this but somehow enjoying it. Getting off on it, even.

“Oh, Kacchan,” Deku moaned, grinding eagerly into his palm.

What the hell. Was the weirdo turned on by mucus or something?

Deku started to wriggle, letting go just long enough to get his pants open. With his cock bared and Katsuki’s sweats safely tugged below his ass, Deku squirmed even closer, coaxing Katsuki’s legs apart to ease himself between them.

“You’re perfect,” he gasped, guiding his dick into the warm nook at the top of Katsuki’s thighs. “I’m so glad I get to do this with you, Kacchan — are you feeling good? I feel so good, you’re amazing, this is amazing… Thank you, thank you Kacchan…”

Katsuki gritted his teeth to hold back a moan. He could feel the full length of Deku’s cock rubbing against him: a teasing brush of skin against his hole, sweet pressure on his taint, the tip nudging against his balls every time Deku rocked all the way in. And Deku’s hand was back too, stroking him in time with his thrusts and smearing pre over the length to slick the way. The feeling worked together with Deku fucking his thighs: firm, deliberate tugs over his shaft, light touches at the crown, pressure against his groin as Deku panted in his ear.

That hot, filthy mouth was always working, mumbling encouragement and pleas and praise. When it opened wider, licking a wet stripe up the column of his neck to his earlobe, Katsuki had no choice but to succumb.

He bit his lip throughout the orgasm, struggling to keep the noises in — but there was no hiding the mess he made of Deku’s hand. His toes curled into the mattress, grounding him, cock spurting hot cum that overflowed from Deku’s fist.

Deku warbled, briefly withdrawing to smear his dick with cum. Then he sped up, fucking Katsuki’s thighs fast and sloppy, sticky hand braced on Katsuki’s hip to keep his legs together.

By the time Deku came all over Katsuki’s thighs with a shudder of delight, Katsuki was boneless and nearly asleep.

Three days later

“I fucking told you,” Katsuki snarled, whipping a box of tissues at Deku’s head.

Deku wormed a hand out of his blanket cocoon to catch the projectile. He smiled blearily, managing to seem proud of himself despite looking like death warmed up.

“Worth it,” he croaked.

Chapter Text

Katsuki didn’t think much of the snot incident at first.

Sure, it was weird. But he already knew that Deku liked to give. The nerd probably got caught up in the moment, made the offer, and didn’t want to back down. It wouldn’t be the first stupid thing he ended up doing out of a lethal combination of impulsivity and a mulish reluctance to change his mind.

The real tipping point came a few weeks later.

Katsuki groaned, digging his heels into the bed for purchase to grind his hips upwards. He felt so good — the slow slide in and out of his ass, hot skin pressing against his cock, the aching stretch deep inside. But it wasn’t quite enough; not what he needed to drive him wild, make him lose his mind with the animal pleasure he craved. With a snarl, he lurched from the pillow to nip at Deku’s earlobe.

“Faster,” he demanded.

Deku was panting loudly, right into his face. His grip had started to slip where both sweaty palms braced on Katsuki’s thighs. He adjusted his hold, sliding his hands to hook under Katsuki’s knees and hoist his legs in the air. Katsuki yelped in surprise as his fingers scrabbled for purchase against Deku’s back.

The new position ground Deku’s cock perfectly against his sweet spot, making his dick drip eagerly onto his belly as he sucked a breath. But although the angle was better — so close to perfect, driving into his ass and making his heart pound and his blood sing — Deku didn’t speed up.

Katsuki growled, dropping his hands to dig meanly into Deku’s ass. “Faster, damn it!” He kept squirming, bucking his hips into Deku’s thrusts in an effort to urge him on. “Is that all you got? I can — gh, can hardly feel you.”

As soon as the words were out, Deku’s pace faltered.

A flash of panic sealed Katsuki’s throat. Had he just royally fucked himself? Was Deku about to pull out, get up and leave him there, blue-balled and dripping pre like a loser?

But before Katsuki could think of a way to bail himself out, Deku moaned.

It was an odd sound: emerging faint and wobbly from Deku’s slack, red lips. But as soon as it happened he moved again, fucking deeper and — yes — faster — tightening his grip on Katsuki’s thighs and spreading them to make room for his driving hips.

Katsuki grinned up at him, flashing his teeth. With both hands resting on Deku’s ass, he squeezed tightly, yanking him in on the next thrust. Thick, hot, hard, deep — fuck, yeah.

“You into that?” Katsuki panted. The adrenaline had gripped him now, spurring him on, filthy words pouring into his head and straight from his mouth. “Said you’re not enough, Deku. Your sss-skinny little dicklet ain’t gonna satisfy me. C’mon — mh! — put your back into it.”

“Kacchan,” Deku whimpered.

His face creased, forehead crumpling and mouth falling open. His cheeks, already flushed, blazed scarlet. Hastily, he leaned down and buried his face in Katsuki’s neck, breaking eye contact. But he did go harder — started fucking deep and powerful, hips slapping against Katsuki’s ass and making the room ring with the sound. Katsuki’s back kept slipping against the sheets, body jerking with each thrust. Deku was going hard enough to fuck him up the bed, if not for Katsuki’s grip on him keeping them grounded.

It felt stupid to call Deku small. He was nowhere close, even before taking his modest height into account. But it didn’t matter: Deku shuddered and moaned all the same, mumbling praises and pleas as he kept on fucking, giving Katsuki’s greedy body exactly what it craved.

Regardless of the truth, the degradation seemed to be working for him.

“Ha!” Katsuki’s sneer cracked into a moan on the next thrust, but he kept his composure as best he could. If this was doing it for Deku, Katsuki was going to put on a fucking show. “You think your shrimp dick can get me off? Fff-fuckin — ah, hah — can b-barely tell it’s there.”

Deku’s cock throbbed. Katsuki could feel it, deep inside him: the twitch of a hammering pulse thrumming through the shaft, beating in time with Deku’s slurring gasps of his name. With a smirk, Katsuki dug his nails into the meat of Deku’s ass, now yanking him in at a punishing pace.

“Are you even in me?” Katsuki moaned. He was delirious with pleasure, toes curling, back arching shamelessly into every driving thrust. “Pa-ah-pathetic. C’mon, work harder. Make me feel your tiny little cock. Put your back into it and give it to me — shit — gimme everything you got. Harder — fuck yeah — fuck me, Deku, fuck me, fuck me, fuck — ah—!”

And before he could even touch his dick, Katsuki came all over himself. It was so sudden, so unexpected and violent, that he was barely aware of what was happening: gone half-blind and trembling with feeling as he shot streaks of cum across his belly.

Deku kept going, carving deep into Katsuki’s ass until his limbs juddered with oversensitivity, that thick cock pressing relentlessly into his prostate on every desperate pass. When Deku finally finished, it was with a whimper, face buried in Katsuki’s shoulder. Katsuki shuddered, muscles drawing to a clench, squeezing around the rush of heat as Deku unloaded himself deep inside.

“Fucking hell,” Katsuki wheezed. His legs slipped from Deku’s sweaty hold to flop on the bed.

Deku grunted, somewhere above him. His body went limp, draped slack and heavy over Katsuki, his cock gradually softening while buried to the hilt inside. Where their chests pressed together, Katsuki could feel the drumming, off-rhythm beat of their hearts.

“You were mean today,” Deku mumbled at length. His face was hidden in the crook of Katsuki’s neck, but he didn’t sound upset.

Katsuki just grinned, stretching his arms over his head until his spine popped. “Yeah, well. You liked it.”

Deku really liked it, if the ten finger-shaped bruises pressed into Katsuki’s thighs were any indication. He winced as he prodded them, examining the damage in the bathroom mirror. Stark red, with purple already blooming around the edges of the marks.

“Fuckin’ animal,” he groused, before slapping the light off and padding to bed in the dark.

Thank fuck, there was little risk of anyone seeing the bruises — not unless some asshole managed to rip his clothes to bits. But it had been a while since Deku got worked up enough to leave marks like this.

Katsuki snuck a look at him: curled up on his side, breathing slow, face smooth and relaxed. He was sleeping like the dead, so deep under that he didn’t even stir as Katsuki settled into bed beside him. Stray coils of hair clung to Deku’s forehead, and he sighed when Katsuki reached out to brush them away.

“What else ain’t you telling me?” Katsuki muttered.

He’d thought their sex life was good. Great, actually. A few weeks back, he’d probably have said it was perfect. But there were still secrets hidden away in that nerdy little head; hidden desires that Deku hadn’t told him about.

Part of Katsuki wanted to feel hurt that his boyfriend hadn’t trusted him — but he pushed the feeling away. It was embarrassing to get off on being told your dick was small. No wonder Deku was reluctant to confess his kinks.

It didn’t matter. Katsuki would figure them out.

Chapter Text

Deku’s hand was hot on Katsuki’s knee.

Huddled in the back of their cab, they were safe from notice. The darkness, the tinted partition and the performative way their driver ignored them worked in their favour. The staff at hero galas could be trusted to take almost anything to the grave — a necessity, when alcohol flowed freely and a bunch of pumped-up pros were set loose.

So, when Deku’s fingers tightened around his thigh, it wasn’t the risk that had Katsuki’s heart beating fast.

Deku had radiated a strange energy all evening, sticking to Katsuki’s back like a shadow. Gaze intense, almost tangible, prickling over his arms and making the fine hairs stand up. It would have made him insane with paranoia, back when he was an idiot and Deku was better at pretending not to lust over him. But after fucking about it enough times to sort their shit out, being stared at just made Katsuki shiver with anticipation.

It always led to good sex.

Sure enough, Deku’s hand shifted. Curled inwards, following the curve of muscle until his fingers squeezed into the hot space between Katsuki’s thighs. With a grin that was lost to the darkness, Katsuki spread his legs.

Deku’s inhale was quiet enough to blend in under the engine noise. But to Katsuki’s trained ear, that soft, sharp sound echoed like a scream.

Four points of pressure dug into his inseam and dragged upwards, following the path laid out for them. Deku’s fingers shook as they went, fear or excitement or arousal or all three. Into higher places, hotter places, brushing distance from the join of Katsuki’s legs. Katsuki sucked in a quiet, anticipatory breath, and—

And Deku paused. His fingers stalled, nestled in the junction of Katsuki’s hip but unwilling to continue. Unwilling to cross that line, even in the darkness and relative safety of the back seat.

So, exhibitionism wasn’t the play. Katsuki crossed it off his mental list, even as he pulled his legs together to trap Deku’s hand in between.

By the time they made it home, muttering thanks to their hopefully oblivious driver, Deku could barely walk straight. He staggered to lean against the wall, dipping his head to press his nose to Katsuki’s neck as he unlocked their front door.

As soon as it closed behind them, Deku crowded into Katsuki’s space. Katsuki let him: breath tight, heart high, dizzy with anticipation.

“Kacchan,” Deku mumbled, hand going back between Katsuki’s legs as if magnetised. He kept pressing forwards, forcing Katsuki to take several stumbling steps back until his hips knocked into the kitchen counter. “Kacchan, you smell so good right now.”

“You think so?”

Katsuki didn’t usually bother with cologne, but it was worth it to get this reaction. He leaned back, letting the counter support his weight as Deku fumbled his pants open. Deku’s head dipped to nuzzle the warm space between Katsuki’s neck and shoulder, inhaling the scent that clung to his shirt. His voice had quietened until it was indistinct, mouth leaving sloppy kisses over every inch of skin he could find and breathing loud like a dog.

And. That was worth a try.

Katsuki grabbed Deku’s tie and pulled, hard enough to tug him away. Deku gasped wetly, neck straining to relieve the pressure.

“Good boy,” Katsuki said.

Deku blinked through a glassy stare.

“Look at those puppy eyes.” Leaning back, Katsuki propped his ass on the counter. “Is that what you are, Deku? Just a big horny dog?”

Deku’s gaze darted away, his cheeks flushing dark as wine.

Got him.

“At least you look good on a leash.” Katsuki yanked the tie again, forcing Deku’s head back until his body was forced to follow. “Wanna put that tongue to work, mutt?”

Deku’s shimmering eyes snapped to meet Katsuki’s. Quickly, he nodded.

Katsuki jerked his chin towards the floor. “Sit.”

No objection; no hesitation. Deku sank straight to his knees, lips parted as if stupefied, waiting silently for Katsuki’s next move. Swallowing a smirk, Katsuki kicked his pants off his feet and slung a leg over Deku’s shoulder.

Deku’s eyes widened. “Kacchan—”

“No barking.”

Deku moaned quietly. His cock strained in his slacks, but he bunched his fists on his knees and didn’t move.

Katsuki couldn’t hold back his leer. “Good. Listen to your master.”

He guided him in, using his grip on the tie to angle Deku’s head between his bare, parted thighs. Deku had gone limp enough that it was easy, head moving obediently wherever Katsuki directed him, mouth falling open as he drew close. He glanced upwards, eyes lidded and questioning, as he gave a gentle lick to Katsuki’s cock.

“Stay.” Katsuki’s head fell back with a sigh. “Yeah, that’s it — lick me all over.”

Deku whined, but kept going. His mouth opened wider, speeding up, tongue lolling to lap soft, flat strokes. It was sloppy: licking all over Katsuki’s cock, down to his balls, tracing the crease at his thigh and bathing his crotch in warm spit. Katsuki groaned between his teeth, letting his hips rock into the lazy, teasing stimulation.

Deku would never normally follow orders this well. This dog thing had its upsides.

“More,” he demanded.

A hand seized his thigh, forcing his foot off the floor as Deku threw both of Katsuki’s knees over his shoulders. The surge of movement shoved Katsuki back until he sprawled across the counter, hips suspended in the air with Deku’s body settling under his legs.

“Shit!”

With his iron grip on Deku’s tie, Katsuki began to yank. He was ready to berate him, to cuss out his disobedient pet and order him back to work — but Deku buried his face between Katsuki’s legs without being told, taking his cock deep in his panting mouth.

“Good boy,” Katsuki huffed. His hold on Deku’s tie didn’t ease, but he reached down with his other hand to stroke through Deku’s messy hair, petting behind his ears with the pads of his fingers. “You want a treat? Want — fuck — want me to give it to you?”

Whatever noise Deku made was garbled. It was meaningless anyway, some pure animal sound of lust and want as he choked himself on Katsuki’s dick. The bob of his head was eager, the slide of his lips wet and frantic — and the fingers that slid up the tendon in Katsuki’s thigh single-minded in their goal.

“Shit!” Katsuki cursed as a wet digit prodded against his hole. “Good boy, fuck, good boy — keep going — gonna—”

Deku’s moan bubbled around the base of Katsuki’s dick as he let a finger sink all the way inside. Katsuki’s thighs tightened around Deku’s head, back bowing off the countertop, and his vision whitened as he came shuddering into Deku’s mouth.

Deku took it as obediently as everything else, deep into the back of his spasming throat as he tried and failed to swallow.

Katsuki’s hearing came back slowly, to the sound of helpless panting. Deku hadn’t moved, still on his knees with cum drooling down his chin, pleading silently with glazed, teary eyes.

“That’s a good dog…” Katsuki lifted his weight onto one elbow, using his grip on Deku’s tie to nudge him back until his finger slipped free. “Trained you well, huh?”

Deku wiped his chin on his wrist, nodding dumbly.

“Want your turn, puppy?”

“Kacchan,” Deku groaned, wet hands grasping at Katsuki’s knees, “please—”

“Did I tell you to speak?”

He whimpered — and it really did sound doglike, high and quiet in the back of his throat.

“Better.” Katsuki let his legs drop from Deku’s shoulders as he sat up. “You wanna play?”

Deku’s eyes blinked once, until they widened as one of Katsuki’s legs pressed between his own. He jolted and moaned, hips bucking automatically to rub into the touch — before Katsuki pulled away.

“Gonna be a good pet?”

Deku’s mouth opened, obviously about to reply until his mind caught up and he swallowed the words. Instead he nodded, pawing rough and clumsy at Katsuki’s legs. Tugged Katsuki’s shin closer and pressed it flush against his hard dick.

He didn’t ask for more; didn’t even try to get closer contact. He stayed down, on his knees on the kitchen floor with Katsuki’s grip solid on his leash, and he humped Katsuki’s shin through his dress pants with a needy, shameless stare.

Chapter Text

It made sense, in a way. Something about Deku had always screamed well-trained pet. The leash, the humping, the good dog — none of it made him pause, and some of it even spurred him on.

And yet the experiment was inconclusive. Too many variables for Katsuki to pin everything on the dog stuff.

You smell so good right now, Deku had said. Maybe he was just turned on by Katsuki cleaning himself up nice? All the stops pulled out, cologne and a suit and whatever other special flairs made Deku’s little pervert head buzz?

Katsuki wasn’t sure. But he could think of one way to test the theory.

He’d always hated feeling dirty. Ever since his awakening, his quirk sweat was amped up, pooling first in his palms then all over his body. Destined to fester and turn stale, unless he kept a constant flow of explosions going to burn it away.

After work it was even worse. Exertion ratcheted up the flow tenfold, and although his costume was made of wicking material, some grime would always linger. Normally, skipping a shower would make him want to gag — but the idea in the back of his mind made him tolerate it. Made him grit his teeth against the instinctive disgust as he put his street clothes back on, uncomfortable over the itch of dried and tacky sweat.

He had to walk quickly as he travelled home so nobody would catch a whiff of him. Luckily, when you were one of the most dangerous heroes in the country with a face built for glaring, people steered clear.

Inside the genkan, Katsuki stripped off his pants and shirt. A glance down his body revealed his battle armour: an ageing pair of boxers he’d been meaning to toss, and an undershirt that was soaked through under the arms.

Perfect.

Deku had come to greet him like the loyal pet he was, fluffy head popping out around the corner. Katsuki closed in swiftly, stalking over to wrap his hands around Deku’s thighs.

“Hey, nerd.”

“Mm, hi.” Deku leaned into the touch, body arching as he stretched upwards — and then froze. His eyes widened, body unmoving save the turn of his chin as he redirected into a chaste peck on the cheek. “How, uh, was work?”

“That all you gonna say?”

Katsuki’s hands followed their natural path up Deku’s thighs, skin twitching and fabric rucking as they traced the thick cords of muscle in his legs. Finally, they landed deliberately on the meatiest part of his ass and squeezed.

Deku yipped, jolting half an inch off the floor. “D-don’t you wanna shower?”

“Hmm.” Deku’s face was angled away, so Katsuki landed a bite on his nose. “Maybe I found something better to do.”

“Oh.” Slowly, Deku turned to peek at him. “I, uh… I thought you wouldn’t want to. You know, after your shift? I thought you’d feel gross.”

Katsuki pulled away far enough to assess him, eyes narrowing. “Do you think I’m gross?”

There was a long pause.

Katsuki was fully aware that he stank. It had been an active shift. Old sweat matted his hair; streaked a salty, half-dried trail down his spine. But Deku’s face slowly flushed as he stood frozen in the embrace, Katsuki’s thumbs on his hips and fingertips digging into the nerd’s ass. When Katsuki tugged him in closer, their hips pressed flush, letting him feel the outline of Deku’s cock through his shorts. Half-hard, just from this.

Deku’s throat bobbed, gaze still glued to Katsuki’s face. “No, Kacchan,” he whispered.

It was enough.

Katsuki backed Deku against the wall, lips first, swallowing the startled noise he made. Startled, but not complaining. Deku’s arms slung over Katsuki’s shoulders, scrabbling to hold him close as their bodies pressed together. Fingers snagged the damp fabric between Katsuki’s shoulder blades, tugging to allow a cool rush of air to soothe his sticky skin. He shivered, forearms prickling with pleasure and relief.

“Hurry up,” he panted, nipping at Deku’s lip.

Deku’s breath left him in a shudder, nails skittering down the length of Katsuki’s back. Rough hands gripped Katsuki’s thighs, hoisting him up as Deku surged to flip their positions. Katsuki grunted, legs wrapping tight — and between his flexed thighs, the wall at his back and Deku’s core strength, it was more than enough to keep them locked together.

Through it all, Deku’s mouth never left his: eager kisses that tugged the breath out of him and made his heart race like he was in a brawl.

“Kacchan,” Deku slurred against his mouth, fumbling at his undershirt.

The fabric was so wet it had to be peeled from his skin. Deku didn’t falter, shoving the vest up into his armpits to bare his damp and heaving chest. Katsuki felt disgusting, all pit stains and threadbare underwear and stale sweat gathered in the folds of his skin, between his pecs, in the hollow of his bellybutton. And yet—

“Woah,” Deku whispered. Leaving Katsuki to hold himself upright, he ran both hands along his torso. “So slippery.”

There was no hint of disgust in his voice. Instead it was reverent: both hands cupping Katsuki’s pecs, sliding against the sweat-streaked skin. His head dipped, hair brushing Katsuki’s gleaming collarbone. Breath puffing damply into his sternum, Deku nosed at the beads of sweat dripping down the middle of Katsuki’s chest. His tongue dipped between his lips, flicking against a nipple as his eyes darted upwards.

Katsuki hissed. Hot wet tongue on hot wet skin; his legs flexed, heels digging into Deku’s lower back and dragging him in. His body shoved close between Katsuki’s thighs, bringing them crotch-to-crotch, Deku’s sweatpants flush against Katsuki’s ratty underwear. Despite it all, they were both rock hard.

“Kacchan tastes so good,” Deku moaned.

He kept rolling his hips in rough, greedy motions, huffing staccato breaths around the loose seal of his mouth on Katsuki’s tit. Katsuki grabbed a handful of curls, making Deku’s eyelids flutter as he shoved the nerd’s face harder into his chest.

“Give it to me,” he demanded.

The room lurched as Katsuki’s weight shifted, making him grab at Deku’s neck for balance. The nerd’s bicep strained, one forearm jammed under Katsuki’s thighs to keep him from falling on his ass, the other hand scrambling with both their waistbands. The casual show of strength was impossible to ignore, but Katsuki closed his lips to choke back the moan. It was too soon to act like a slut.

Instead he ground down onto Deku’s bare cock, letting it slot in the cleft of his ass.

Just like the rest of him, the skin there was slick with sweat. Easy to move against each other; easy to rut. Deku’s face stayed crushed against Katsuki’s chest, both hands supporting his weight once again, tilting his hips for a better angle to fuck haphazardly between Katsuki’s ass cheeks.

Katsuki groaned through his teeth. The scent of his own body was hot in his nose, musky and sharp. The smell of power and hard work. His arm slapped against the wall above him as he seized his cock in his fist.

“You like this?” he panted.

Deku moaned wordlessly, head wobbling a half-nod as he dragged his tongue across the scarred stretch of skin spanning Katsuki’s chest, lapping at the salty residue. His cock throbbed against Katsuki’s ass.

“Yeah?” Katsuki arched his back, shoving his torso further into Deku’s face. “You like how I smell, Deku?”

Deku’s lips parted on a huff, smearing spit that mingled with the moisture on Katsuki’s skin. “Uh huh,” he mumbled.

“Gross.” Katsuki released his cock to bunch a fist in Deku’s hair, keeping him from pulling away. “Keep going — lick it all up.”

A grunt melted into a moan, Deku’s hands gripping tighter at Katsuki’s ass as he continued to rut. His tongue lolled from his mouth to drag, slow and deliberate, across the full breadth of Katsuki’s chest, gathering stale sweat and leaving a glistening trail behind.

“You’re so fucking nasty,” he breathed in awe. “Want more?”

Deku pulled away to lick his lips, eyes lidding at the taste of salt. “Want all of Kacchan,” he rasped.

Katsuki grinned. Time to put his hypothesis to the test.

Deku’s breath stuttered as Katsuki’s grip tightened on the back of his head. Pre smeared into Deku’s hair, coiling between Katsuki’s fingers as he aimed Deku’s open mouth right where he wanted it.

Right into the hot cavern of his sweaty armpit.

Deku’s yelp was startled, body jolting in an instinctive attempt to escape. His mouth opened, lips half-formed around whatever words he had planned—

And his tongue slid along that sensitive stretch of skin.

Katsuki spat a curse, thighs squeezing around Deku’s hips. It fucking tickled: a slurping tongue where it had no right to be, hot and strange and gross. Almost too much, almost enough to make him shove their bodies apart and abandon the whole thing — until Deku, face ruddy and trapped in his pit, let out a moan.

It vibrated against Katsuki’s flesh, so sensitive it sent shocks through his gut, as Deku’s body fell back into steady, rhythmic motion. His tongue lolled from his mouth, sweat-drunk, eyelids heavy. One hand trapped under Katsuki’s weight, the other groped frantically to find his cock again.

“Fuck!”

Katsuki jolted at the rough touch, head thudding against the wall. Deku’s tongue was maddening, so fucking slippery and sensitive, matching the eager pace of his thumb smearing pre in sloppy circles around his crown. Trapped in the crack of Katsuki’s ass, his cock pulsed and throbbed.

“Fuckin’ — dirty perv,” Katsuki huffed, caught squirming in the claws of sensation. “You like my sweat, huh?”

Deku moaned wordlessly, head bobbing in eager mindless nods. Katsuki gripped his hair harder, heels digging into Deku’s back, arching simultaneously into and away from the assault.

“Knew you’d like it,” he groaned. “You’re a freak, always have been. Even when you tried to hide it, I knew. Knew you were a — fuck — a kinky bastard. A weirdo. A — ah — fucking shit!”

Cum spurted hot over his stomach, forced from his body by the relentless stroking of Deku’s palm and the insane feeling of being tongue-bathed by an eager pervert. Deku’s moan came sloppy between stuttered breaths: always matching intensity, matching the pace. His cock throbbed, trapped in Katsuki’s ass crack, painting his back and dirtying him even more.

Katsuki stared sightlessly at the ceiling, chest heaving as he struggled to catch his breath. Why the hell did that feel so good?

When Deku lifted his head, it left Katsuki’s armpit feeling damp and weirdly cold. His legs shook when Deku lowered them to the ground, leaving him hanging from his grip on Deku’s neck.

It took a minute to gather his thoughts.

“Kay,” Katsuki croaked eventually, arms slithering loose. His thighs still wobbled, but he had a nerd to impress. “Gonna shower.”

“Um.” Deku blinked at him, eyes unfocused. Half-dried sweat coated his chin and halfway down his neck. “O-okay. Do you… want a hand?”

“The hell’s the matter with you?” Wetness smeared as Katsuki shoved Deku’s face away. “I’ve got boundaries, loser.”

Stunned into silence, Deku watched him all the way to the bathroom.

Chapter Text

Test after test, trial after trial. Nothing changed. It didn’t matter what he did; what weird or gross thing he threw Deku’s way that would make any normal guy’s dick deflate in a second. Deku rolled with every punch: always eager, always turned on. If there was something out there that didn’t make Deku horny, Katsuki was struggling to find it.

The thought rankled. Not enough to interfere with their sex life, but enough to fester.

How long had Deku planned to keep his fetishes secret? In all their time together, Katsuki had never even got a glimpse of the depravity lurking below the surface. Each new discovery was a secret unearthed, a hidden truth that he’d had to dig to find.

Considering how much Deku struggled to keep secrets, he’d done well to hide this one as long as he had.

There was a dopey expression that Deku only wore when Katsuki got on top. A blotchy flush in his cheeks, a lopsided droop of his eyelids, mouth hanging slack and gaping.

It was probably the view. The position offered what they both knew was a great show.

The extra effort was worth it to watch Deku struck dumb, mesmerised by the flex of Katsuki’s thighs and the rhythmic bouncing of his chest. Even his hands, normally greedy to touch as much as he could, rested loosely on Katsuki’s knees, clammy and impotent.

Yeah. He had the nerd in the palm of his hand as well as the grip of his ass.

An aggressive motion of Katsuki’s hips made Deku gasp. His fingers flexed enough to dig into the flesh, mouth widening to suck in air — and his eyelids, already heavy, fluttered shut.

Moving too fast for his brain to catch up, Katsuki landed a swift smack to Deku’s face.

Deku’s eyes shot open as a startled yelp punched from his lips. The slap was hard enough to sting, not hurt, but the pink glow on his cheek showed that he was feeling it.

“Oi,” Katsuki cut in before Deku could muster a word. “Eyes up here.”

Deku stared at him. Cogs were turning in his over-analytical nerd brain; Katsuki could see the whirring behind his wide, stunned eyes.

Despite Deku’s shock, his erection hadn’t flagged at all. It wasn’t surprising, at this point.

Still panting, he slid his hands from Katsuki’s thighs up to his hips, keeping his gaze fixed deliberately on his face. “Y-yeah,” he managed, sweaty throat bobbing. “Uh. Sorry.”

“Good.”

Katsuki resumed his pace, letting his hips grind to and fro to rock the dick inside him. One thing that never changed: no matter what kink they tried, sex with Deku felt fucking great. It was the only thing keeping him going, at this point.

That and Deku’s dazed, dewy-eyed face, gazing at Katsuki towering over him and gasping like a fish drowning in air. That was fun too.

“Y’know,” Katsuki began, making sure to keep his tone casual. “Most people don’t like getting smacked. At all, but especially during sex.”

“A-ah, well…” Deku licked his lips, eyes sliding to the side.

“But you never ran away from pain.” Katsuki’s hands landed softly on Deku’s chest, fingers splaying. “Right?”

Deku grunted as one hand slid, slow and purposeful, to his nipple. It pinched gradually, enough to tease then to tug, twisting meanly on the release and leaving the bud hard and dark.

“Kacchan,” Deku gasped. His hips rocked steadily, keeping the pace going while Katsuki was distracted with the game.

“You can handle it.” Katsuki cast a glance up at his face. “Don’t mind a bit of punishment, yeah?”

His other hand crept across the opposite side of Deku’s chest, reaching around to brush the vulnerable expanse of his ribs. The flesh there was tender, relatively unprotected by muscle or fat.

A sudden, sharp pinch made Deku grit his teeth.

“N-no,” he managed. Sweat streaked his forehead, soaking into his hairline. “Not when — gah!”

Katsuki grinned around his mouthful of pec. “Mm?”

Deku squirmed as Katsuki sucked hard. The skin heated in his mouth, caught between his jaws and forced to swell until it ached. “Not when it’s worth it. Kacchan—”

Katsuki sat up again, letting his teeth drag and forcing a keening noise from Deku’s throat. The area left behind was bright pink, warm and shiny from his mouth’s abuse. His cock jumped: the mark looked good.

His hands settled again over Deku’s chest, one on each side to encompass its breadth. Fingertips resting just under Deku’s collarbones, the meat of his pecs cupped snugly in Katsuki’s palms.

“C’mon, hero,” he said, willing the blood into his hands and letting them heat. A faint sizzle filled the room, followed by Deku’s hoarse moan and the scent of singed skin. “I know I’m worth it.”

Flushed and sweaty, tears glistening in his eyes, Deku spread Katsuki’s cheeks apart and got to work making him see stars.

Chapter Text

There was something about the night before a day off. Anticipating the time that lay ahead; knowing that patrols and paperwork and dumbass civilians were in the rearview mirror, at least for now. Being free, for the first time in a while, to do whatever the fuck he wanted.

Including getting dicked however the fuck he wanted. If he walked with a limp tomorrow, it wouldn’t matter.

Deku’s fingers flexed where they gripped Katsuki’s waist, hips pummelling a sloppy beat against his ass. “Kacchan,” he slurred.

Katsuki grunted, one hand braced against the headboard to keep from concussing himself. “Harder.”

“Kacchan,” Deku repeated, hammering away at the same steady rhythm.

“You listening?” Katsuki would have set off a quirk-bang to get Deku’s attention, except his other hand was occupied with his cock. “Harder, ‘m getting close.”

“Kacchan.”

Still no change. Each stroke grazed his prostate, almost but not quite, and it was starting to fucking annoy him. Katsuki squirmed in the vice grip on his waist, reaching back to try and grab Deku’s wrist — and suddenly he moaned, voice slurring.

“Oh — Ka-ahh-chan.”

Katsuki’s brain stalled. 

Deku hadn’t noticed anything. Somehow. Or at least, he was still going, almost braining Katsuki on the headboard until he slapped out a hand to catch himself once again. It was like nothing had happened; like Deku didn’t just slip up and reveal another secret fetish.

Again.

This one was unexpected. Not that any of them had been on Katsuki’s radar before this whole ordeal started, but he could never have guessed this in a hundred years.

Kaachan. Mommy. Gross.

“You wanna make me a mommy?” he blurted, before his brain could modulate the words.

Deku’s pace stumbled. Stopped. His fingers flexed sweatily on Katsuki’s waist.

“Huh?”

Katsuki turned his head, squinting back at Deku with eyes narrowed against dripping sweat. “That do it for you? You wanna knock me up?”

Somewhere behind Deku’s dumbstruck expression, wheels began to turn. Katsuki could almost hear the gears creak into motion.

“Get Kacchan pregnant,” Deku mumbled under his breath. Slowly, he began fucking again.

Well, shit. Katsuki was a lot of things, but he wasn’t a quitter.

“Do it,” he gritted out, letting his head hang as he ground back into the rhythm. “Want you to — ugh — shoot inside me and fu — fill me with your seed.”

Even though he’d been close, the words were almost enough to make his boner die on the spot. Still, he managed to get the sentence out without cringing — and while keeping half an eye on Deku behind him, scrutinising his reaction.

Deku didn’t seem to have the same problem. Red-faced, forehead crumpled, he kept going, huffing loudly as he picked up the pace.

“You’re being so good for me,” he wheezed. One of his hands crept from Katsuki’s waist around to his front, petting his belly almost reverently. “Look how well you take it, sucking me in like this… Milking my cock like you’re meant to be bred.”

Katsuki winced, but a well-timed thrust to his prostate turned it into a moan. On a normal day, he’d never have touched this kink, but this wasn’t normal and neither was Deku. The experiment was all about testing the nerd’s limits; finding the places that even his ravenous libido wouldn’t go.

So:

“Knock me up,” Katsuki growled back, turning away so Deku wouldn’t see his gritted teeth. “Hurry up and fuck me pregnant. Fucking — gimme your cum.”

With a pained groan, Deku hiked Katsuki’s hips higher, planting a foot on the mattress for leverage. The position sent his cock barrelling deeper, lavishing attention on Katsuki’s prostate and forcing him to fuck his hand where it still gripped between his legs. The sensations swept through him, making his eyes roll and his jaw go slack — and stripping any chance to react to the flood of bullshit Deku was spewing.

“Gonna breed you so good, Kacchan,” he babbled. “Gonna fuck you like this every night, just like you want, stuff you so full you can’t walk. Until you get big and round and… and your tits leak milk. Mmh, gonna make you a mommy — gonna — gonna fill up your womb—”

“What,” Katsuki managed, right before he came.

It was the weirdest orgasm he’d ever had. It felt fantastic, all quivering legs and gasping moans and surges of pleasure that painted messy streaks on their bedsheets. But the emotions made it hard to process, his mind reeling too much to really enjoy the sensation. Behind him, Deku shoved his face into his back and grunted, pumping his hips, filling him up as promised.

Katsuki slumped into the mattress. The cotton sheets rubbed against his cheek.

Even when Deku pulled out, Katsuki didn’t move. His thighs burned and his ears were ringing, almost drowning out the shuffling sounds around him. Finally, something cold and slick nudged against his leaking hole.

“There,” said Deku as he pushed the plug in. He gave the base a little pat with his fingers. “To make sure it takes.”

Then he moved away again, humming tunelessly. He didn’t attempt to move Katsuki, simply cleaning around him: mopping up spills, straightening the bed, putting the lube away.

For once, Katsuki might have appreciated having his afterglow disturbed. The further his high receded, the more room his emotions had to take root and grow. Shock. Confusion. Anger. This shit was not what he signed up for. He’d assumed — he’d believed — that there were limits.

The nerd should have come with a fucking waiver.

Slowly, Katsuki pulled his legs under him to sit up. As he straightened, a muscle in his lower back twinged, sending a spasm down his legs and shoving the words from his mouth.

“What about piss?”

Deku dropped the towel. For a second he didn’t move, his back rigid as he stood, hunched, over the sink.

“W-what about piss?”

“Does it turn you on.” Katsuki gestured, a jerking movement that encompassed all of Deku’s body. “You know, since we never talk about this stuff?”

“Uh.”

Deku’s eyes darted all around the bedroom, looking at everything — everything — except for Katsuki.

Fucking great.

“I suppose… I’m open to it.” Deku shifted from foot to foot, still framed awkwardly in the bathroom doorway. “Um. I never really thought about how to do it, though. Put a towel down I guess, or maybe we’d have to do it in the bath? It would be messy, but, uh. That’s okay. So, I mean, if it’s something you’re into then—”

“If it’s something I’m into?” Katsuki interrupted. “You just said you’d do it!”

Deku stared at him. “But… Kacchan, you’re the one who asked me.”

“I DIDN’T ASK!”

It burst out of him — the growing shame bubbling up Katsuki’s throat and spewing out like tar. For some godforsaken reason, he just came his brains out while Deku blabbered on about his fucking womb. How the fuck did his life come to this?

“I didn’t ask for any of this shit,” Katsuki snarled again, scrambling to his feet — and. The motion jostled that fucking plug, still stuck in his ass, a grim, silicone reminder. With a howl of rage, he yanked it out and hurled it across the room.

The plug flew in a glistening arc, trailing fluids like the tail of a comet. Deku’s gaze followed it until it hit the wall with a splat.

It felt like a full hour passed before Deku managed to close his mouth again. “Kacchan, what the hell?”

Katsuki panted, standing with his knees splayed like a cowboy with a sore ass. Cum trickled steadily down his inner thigh.

“Look,” Deku said. His eyes closed just too long to be a normal blink. “It’s late. I don’t know what I did, but — never mind. Doesn’t matter. I’ll sleep on the couch tonight.”

And with that, he grabbed his toothbrush from the sink. He paused, giving Katsuki one more look, before padding into the hall and closing the door behind him.

With the finality of the latch clicking into place, it was hard for Katsuki not to feel like he made a huge mistake.

Chapter Text

A slice of sunlight glared across Deku’s face, bifurcating his scrunched-up forehead. Despite his awkward sprawl, feet dangling off the couch and head turned at a painful angle, he seemed dead asleep. Katsuki paused in the doorway, ribs contracting to squeeze his lungs with a guilty grip.

In lieu of using his words, he woke Deku by cooking loudly.

“Mornin’,” came the mumble a few minutes later. Bare feet padded closer until Deku stopped — close enough to sling his arms around Katsuki’s waist, but without touching.

Katsuki’s fingers flexed around the handle of the pan. They needed to talk. He knew they needed to talk, but where was he supposed to start? How could he confess that he didn’t share Deku’s kinks, after so much time playing along and giving him the wrong idea?

Shit. Deku was going to be so disappointed.

The fish had begun to curl, revealing hints of golden brown at the edges. Steeling himself, Katsuki flipped the fillets, switched off the stove and turned around.

“Hey,” he began. Hey was good. Neutral.

Deku peeked at him, lips curling into a tense smile. The couch cushion had left a long, pink imprint in the side of his face.

Katsuki barely suppressed the urge to roll his eyes, instead leaning in to give him a kiss on the cheek. Way too mushy, usually — but the way the nervousness drained from Deku’s body proved it was the right call.

“Kacchan,” he said, taking a step and a half back until he could meet Katsuki’s gaze again. His hand lifted, daring to linger on Katsuki’s arm. “Obviously… something happened last night. I — honestly, I don’t get it, but I know you were upset, so. I’m sorry.”

Katsuki sighed, shoulders slumping. It was hard to hold onto the scraps of his pride after cleaning lube off the wall. “Me too.”

Deku squeezed his bicep, still looking at him so fucking tenderly. “Can you tell me what happened?”

Just like that, tension radiated through his spine once again — but Katsuki fought it off. Jerked his chin at the rice cooker, muscle tight in his jaw. “Eat first. Then talk.”

Deku scuttled off to pile rice into bowls.

With their breakfast plated, they sat at the table. Wisps of steam curled into the air between them, obscuring Deku’s face as he shovelled food into it between vague complimentary noises.

Katsuki poked at his fish, words wrestling at the back of his tongue. Talking was easier said than done, sometimes.

“Got frustrated,” he said eventually, when he knew Deku’s mouth was full. “All this shit — our sex life, it’s pissing me off.”

“Mm.” Deku struggled to swallow, cheeks bulging. “I don’t understand why,” he managed eventually. “I don’t always get it right, but I’m doing my best. It’s hard to keep up sometimes, you know?”

Katsuki stared at Deku. Deku stared back.

“Hah?” said Katsuki. It was the only thing that came to mind.

“You know?” Deku said again. Tiny bits of food fell on the table as he gestured with his chopsticks. “All that stuff you want. It’s just new to me. I don’t know if I’m doing it right. Like the small penis thing, the breeding, the puppy—”

“Stop,” Katsuki interrupted. Partly because he never wanted Deku to say breeding ever again, but mostly because his eyeballs felt like they were being microwaved in their sockets. “The fuck do you mean, I want it? Deku — I did that shit for you.”

“For me?” Deku’s shock didn’t look staged. His mouth hung open like a cartoon, a grain of rice clinging perilously to his chin. “But… huh? I mean, why? I never asked you to do anything, so why would you…?”

“That’s why it was so fucking annoying!” Katsuki snapped. “You wouldn’t tell me so I had to guess, fucking… solve riddles to figure out what gets you going, and — it all did. Everything! For a horndog you sure are a fuckin’ coward.”

“I…” Deku’s mouth worked helplessly around scraps of words. Eventually he settled on, “Why did you think I wanted any of that stuff?”

“Because you did!” Katsuki slammed his chopsticks down, pointing an accusing finger. “Quit acting innocent, scumbag. You enjoyed everything I threw at you.”

“You did it during sex!” Deku cried. “If you ask me if I like something while my penis is in your butt of course I’m gonna say yes!”

“Wh — don’t be gross!”

“Then don’t be weird!”

Katsuki blinked, speechless.

“Deku,” he said slowly.

But Deku began to laugh. Quietly at first, then louder and louder as the mirth gripped him, seizing every limb with painful spasms. He doubled over, elbow propped on the table to keep from falling, laughing so hard his bed hair quaked.

“Kacchan,” he rasped, then had to pause as another wave of laughter swept his body. He gulped it back, helplessly banging at his chest. 

Katsuki gaped at him. “The fuck’s your problem?”

“I — I thought—”

But the words wouldn’t come. Wheezing like a dying animal, Deku rummaged in his pocket for his phone. After a few seconds of frantic tapping, he turned the screen to Katsuki.

“Izuku, what’re you—”

“Just look,” Deku insisted, hoarse from laughter.

Katsuki leaned closer, squinting to read the text. “Boyfriend insulted my penis? What the hell… Small penis humiliation, boyfriend secret fetish, how to please my kinky boyfriend…”

Realisation struck like a kick to the nuts.

Dishes rattled as he lunged across the table — but Deku evaded easily, anticipating the attack. When he crossed his arms to shield his face, Katsuki grabbed him, one hand clamped on Deku’s wrist as the other clawed for the phone.

“I needed advice!” Deku yelled, forearms twisting in a vain attempt at escape.

“You couldn’t even use incognito?” Katsuki hollered.

“I was panicking! I just wanted to make you happy, but…” And Deku’s face creased with laughter again. “This whole time, you — you thought you were indulging me—”

The force of that was enough that Katsuki’s grip slackened. Sensing the opportunity, Deku wriggled from his grip like an eel.

It took some time to process before Katsuki remembered to glare again. “Fucker,” he muttered half-heartedly. “I wasn’t indulging shit.”

But that was a lie, and they both knew it.

Deku stood to touch Katsuki’s cheek, not even flinching as his phone clattered to the floor. “I love you,” he said sincerely.

Even after hearing them countless times, the words still sent a jolt through Katsuki. He turned away, ducking out of the touch with his ears flaring. “You’re just saying that ‘cos I humiliated myself.”

Deku gave that the attention it deserved by ignoring it.

“You’re what I’m into, Kacchan,” he insisted. He padded closer, stepping around the table to close the gap between them. “Just you. Your face…” He began to shower Katsuki in kisses, tracing the breadth from his smooth cheek over the bridge of his nose and across to the ridges of his scar. “Your eyes. Your expression when you’re feeling good, oh my god.”

Katsuki turned his face up to meet the next one, ambushing Deku with a kiss on the lips. “Gross.”

“Your voice,” Deku continued dreamily. “Your body.” He was touching now, stroking up and down Katsuki’s flanks through the fabric of his tank top. “Do you even know how hot you are?”

Katsuki stood, right into the waiting circle of Deku’s embrace. “Dunno,” he smirked. “Tell me.”

Deku’s eyes lit up. “You’re perfect. You’re so strong, but you’re slender in all the right places too. Like your waist.” His hands shoved under the hem of Katsuki’s tank, pawing at him to demonstrate. “See? It’s so small compared to your shoulders, your arms. Your chest.” He pushed the fabric up under Katsuki’s armpits and sighed happily. “There they are.”

“What the fuck is they—”

Deku, the piece of shit, just leaned down and sealed his lips over a nipple. Katsuki’s hips jumped, an involuntary moan escaping.

“Beautiful,” Deku mumbled around a mouthful of tit. After a greedy suck, he popped off, leaving it wet and ready for his fingers to play with. “And so sensitive. I love feeling you in my mouth, you know? Your nipples going hard, your chest pushing into my face. Hearing you when you’re feeling good. I could die happy like that.”

“Fuck you,” Katsuki choked out through a thick throat. “You ain’t dying.”

Deku didn’t respond. Heavy-lidded and dark, his eyes stayed trained on his work as he toyed and tweaked with Katsuki’s chest. His breath came fast, cheeks flushing, a stupid boner forming in his stupid shorts.

Impulsively, Katsuki grabbed it.

“Woah!” Deku teetered, catching himself with a clasp on Katsuki’s shoulder.

Katsuki grinned at him, letting his fingers slowly flex around the bulge at the join of Deku’s legs. “Keep going. Somethin’ about my voice?”

“Mmn. Yeah. Your normal voice is — rough.” With Katsuki’s fingertips curling one by one around his shaft, every syllable from Deku’s mouth was a struggle. “L-loud. And that’s… mh, that’s sexy too. It’s how you sound during fights, and I love that side of you. Always have. But — hah…”

His knees wobbled as Katsuki’s thumb pushed against the head of his cock. His teeth scraped his lower lip, painting a bold white stripe through the pink.

“Y-your voice is different during sex,” he forced out. His fingers still lingered on Katsuki’s chest, movements slow and distracted. “It goes all smooth and — and rich. Mm. When you feel really good it gets higher, and I can tell from your breathing when you’re close. When you’re about to come. The way you say my name—”

“Izuku.”

Deku’s eyes dragged their way up, lingering on every inch between Katsuki’s nipples and his face.

“Talk’s cheap.” Katsuki hooked two fingers into the top of Deku’s shorts, baring his teeth in a grin. “C’mon.”

He led the way to the bedroom, eighty kilos of buff nerd trailing after him, grip strong around his wrist. It didn’t shift even as Katsuki turned to face him; as he shuffled back blindly into the bed and kicked his sweats off over his ankles. He sank into the mattress with Deku above him, pulling him down by the face to press their lips together. Deku moaned, sagging until all his weight pressed into Katsuki, licking clumsy and eager at his parted lips. His dick jutted between them, knocking awkwardly against Katsuki’s abdomen, until he held it in place with a hand shoved abruptly down Deku’s shorts.

“Kacchan—” Deku gasped into his mouth.

Katsuki hooked his feet around Deku’s thighs, locking his body in place. “Show me how much you want me.”

The lube was easy to grab, left out on the bedside table from the night before. Slick fingers slid into his ass, one then two, pressing and curling with tender precision. It felt stupidly good — Deku’s fingers always did. Katsuki mouthed mindlessly at Deku’s shoulder, breathing in the taste of his skin, shivering around the stretch until the fingers withdrew and left him hollow and needing.

Deku sucked in a breath, shifting to prop himself on one arm. His gaze didn’t shift from Katsuki’s face as he reached down to fumble his cock from his shorts, messy hand leaving smears of lube on his front.

Heat shot from Katsuki’s head to his gut. Swallowing heavily, he went to turn over — until Deku caught him with a palm on his thigh.

“Wanna see you,” he murmured.

It hadn’t been long. Deku nudged inside easily, hands hooked under Katsuki’s ass to angle his hips up, darkened eyes still pinned on his face. Even trying to swallow the moan, it spilled out with Katsuki’s next breath.

Shit. It felt so right having Deku fill him like this.

It was clear Deku was feeling the same. Uneven blotches of pink stained his cheeks, thighs quivering with feeling. “Kacchan — you’re perfect.”

Katsuki didn’t reply, crossing his ankles as his arms mirrored the motion to wrap around Deku’s back.

Deku’s thick arms braced on the mattress, framing Katsuki’s ears. He tossed his head, attempting to shake the hair out of his eyes and failing as more locks fell right back into his face. The tendons in his neck jutted sharp. “C-can I move?”

“Slow.” Katsuki’s thighs splayed wide to make more room between them, limbs drawing tight to bring them so close their cheeks brushed. “Let me feel all of you.”

Deku moaned, voice reedy. His eyes threatened to close, but he forced back the urge, tenderness swimming in his gaze. His hips rocked: pulling back almost all the way, almost enough to slip out, until the head tugged at Katsuki’s entrance and made him twitch at the pull. Then back in, just as slow as the first delicious push, bumping against his prostate and right down to the root. Hot skin against skin, Deku’s hips grinding just so against his ass.

“Feels good?” Deku huffed in his ear.

“Fuck off.” Katsuki grabbed Deku’s neck with one hand and his own dick with the other. “More.”

When Deku obeyed, Katsuki’s toes curled. Fuck — the slide, the drag, the stretch on the edge of too much. Deku’s cock wasn’t pretty: thick and heavy and slightly curved, oddly clashing with his body and crowned with a messy thatch of pubes. But it was built for fucking. It had Katsuki leaking all over his fingers already, grip slippery where he tugged mindlessly at himself.

“Love you.” Deku kept a steady pace, bent down to nuzzle his cheek in Katsuki’s neck. “Just you. Always you, all of you, like this…”

“Mngh,” was all Katsuki could manage. Deku’s cock filled him completely, pressing so deep he could taste it in his throat. The weight of his body was almost stifling, pressing air from his lungs — but Katsuki wanted more. Wanted him closer. Somewhere along the way, between the mucus incident and breakfast that morning, Deku infected him with sentimental nerd disease.

“Kacchan,” Deku warbled, lips smearing over his chin, “so good.”

Sweat pooled between the heated skin of Deku’s neck and the palm of Katsuki’s hand. He gripped harder, still jerking himself off with the other, all sweet sweat and inevitable pooling need.

“Fuck,” he gasped, and “Izuku,” instead of you feel incredible or love you too.

He didn’t need to. Deku reacted as if he’d heard the words aloud, moaning and shivering through an obvious peak. Katsuki jolted, ground his hips into the pulsing heat, and came over his stomach in a sticky mess.

The weight on top of him sagged. Deku had gone limp, breathing heavily into his ear. With the hand still cradling the base of his skull, Katsuki allowed himself to pet him, running fingernails to and fro to scratch at Deku’s nape. He made a soft sound of pleasure and kissed the curve of Katsuki’s shoulder, easing his hips back just enough to slip free.

His breath left Katsuki’s shoulder damp when he spoke. “Did I prove my point?”

Katsuki hummed. “I guess. You didn’t try any freaky shit, anyway.”

“See?”

Deku’s hair needed washing. Its scent was strong where it pressed against Katsuki’s cheek; where it curled, dark and heavy between his fingers. The nerd melted slowly under the touch, lips pressed against his skin and leaving warm, moist traces of breath.

“Although,” he said, and then stopped.

Katsuki’s eyes snapped open. “What?”

“Nothing!” The shame was immediate, Deku’s head ducking to burrow against his sternum. “D-don’t worry about it, let’s just enjoy the moment—”

“Izuku. Are you gonna tell me you actually have a secret kink?”

He gulped, arms tightening around Katsuki’s waist. “It’s not a kink… exactly? It’s just… something I think about. Sometimes. Not every time. Hardly ever, actually, if I’m being honest. Haha. It’s just that, well, I have thought about it and, um, wondered. If you’d be willing to try. But! I wouldn’t want to put any pressure on you, and it’s weird anyway, so—”

“Deku.” Katsuki hauled him up with an iron grip on Deku’s neck, manhandling him like a guilty puppy. “Weird ain’t shit. At this point, I can handle anything.”

“...Okay.” Deku disentangled their limbs to sit up, gaze cast demurely downwards as his fingertips tapped together. “Well, I was thinking about a sort of… hero roleplay? Like, All Might and the civilian he saves, or. Yeah. I’ve had that sort of fantasy ever since I was a kid, but… I mean, it’s kind of weird now that we actually know him. Um. And anyway, I figured it wasn’t your thing.”

“It’s nerdy as hell,” Katsuki confirmed.

Deku wilted. “Yeah.”

“But so are you,” Katsuki declared. “And it ain’t as bad as pretending to be a mommy. Never again, by the way.”

Deku’s ears turned scarlet. “I thought it’s what you wanted!”

“You’re an idiot.” Katsuki hauled himself upright, spine cracking loudly as he stretched. “But fine. Let’s try your cheesy All Might thing sometime.”

Deku grinned like the goofy nerd he was.

Izuku grimaced at his reflection, trying to smooth the creases in his shiny skintight jumpsuit. All Might’s bright colours didn’t exactly suit his complexion, and the sick look of nerves on his face made him appear more constipated than heroic. He took a long breath, trying to steady his heart.

“I am here,” he murmured, then tried again in a deeper register. “I am here. I am here…”

He still couldn’t believe Kacchan had agreed to indulge this fantasy. Kacchan was the best at sex. Sure, it came after weeks of being ambushed with bizarre surprises, but still. Izuku was the luckiest guy in the world.

“I am here!” he rehearsed under his breath one last time, flashing his All Might smile in the mirror. Picture perfect, as always. That skill would never fade.

With a final nervous tug at his spandex wedgie, he stepped into the bedroom.

“I am—!”

The words died.

In the middle of the room was Kacchan. That was fine. Expected, actually. Izuku would have been pretty disappointed if Kacchan hadn’t shown up. No, what bothered him was—

“What are you wearing?” Kacchan bellowed.

“What are you wearing?” Izuku fired back, pointing accusingly. “I said All Might and a civilian!”

“I know! Why’d you think I bought this?” Kacchan gestured at himself. Under the fabric stretched taut across his chest, his pecs wobbled.

They stared at each other, twin All Mights in matching uncomfortable tights.

“Well,” Izuku said weakly after a moment. “I should have been clearer, so. That’s my fault. Maybe you can return it?”

Kacchan’s eye twitched.

“Um.” Was All Might’s real costume this suffocating? Izuku could barely breathe. “I’m sorry…?”

“Get on the bed,” said Kacchan, voice flat.

“Uh. Huh?”

“Get on the bed!” Kacchan lunged at him, tugging at the neck of Izuku’s jumpsuit. “After all the effort I put into finding this thing, you wanna back out? Think you’re too good to roll with the punches, huh? Fucking nerd—”

“Why would there be punches?” Izuku cried, before Kacchan’s rough palm smothered his mouth.

“Hope you’re not on duty, All Might.” Above him, a silhouette loomed, outlined in garish red and blue. “Because I am here and I’m gonna show you who’s the real number one.”