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Kirishima’s stretching on the other side of the agency gym.
Katsuki’s on the treadmill—a light jog to cool-off after his workout. The line of treadmills conveniently overlook the open mat area, giving Katsuki a clean, unobstructed view of Kirishima, bent in half, the keyholes in his hamstrings in stark definition.
He’s just—stretching. It’s normal. It’s a normal, healthy thing to do. Katsuki understands this.
But what no one told Kirishima is that his shorts are just a little fucking see through. And when he’s bent over like that—Katsuki can see the chubby outline of his pussy, tiny between the thick muscle of his thighs.
He’s so—small there. It’s insane.
Katsuki, over the years, has become accustomed to the raw physical presence of Kirishima. Broad shoulders, thick waist. Arms the size of Katsuki’s head. He’s even shot up in height in the last few months, knocking shoulders with Iida and Shouji.
All that is without his quirk. Unbreakable turns him into a mountain. He’s inimitable. He never bows, never breaks, never falls.
But here Katsuki is. Looking at the sweet little sanctuary between Kirishima’s legs. The one soft piece of him.
He imagines—taping it open. Chubby lips pinned back like butterfly wings, letting that tiny pussy drip everywhere, with nowhere to hide. Kirishima would be—mortified, probably, begging Katsuki to stop, puppy dog eyes turned up to a thousand.
It’s his fault, anyway. Katsuki’s just reacting.
Kirishima straightens up. Swings his shoulders back. The muscles ripple beneath his compression shirt.
Katsuki ups the incline, and begins to plot.
It’s Hagakure’s birthday that weekend, so they have a little party at her place. Every spare surface in the living room is crowded with bottles and shot glasses, and the kitchen table has been repurposed for beer pong.
After the obligatory cake-cutting and present-opening—Katsuki got her the gym set she’s been eyeing, and she throws herself across the room so thank him—the party devolves into loud music and dancing.
It’s Ashido’s apartment, too, so of course the place is decked out in LEDs, a disco ball, and industry-standard speakers.
It makes for a good party, which is what Katsuki can admit to himself, but will never share with her. Ashido doesn’t need any kind of validation for her ridiculous—bordering on offensive— spending habits.
“Bakugou!” Kirishima crashes down next to him, bouncing a little on the couch. “Heyyy, man!”
“You’re drunk,” Katsuki observes, amused. “You good?”
“Yeah! Won my first two games, obviously, me and Kami are, like, the dream team—but then Todoroki kicked Midoriya off his team and called Sero up and, well, he’s—he’s so annoying—I feel like he’s cheating somehow—”
Kirishima groans into Katsuki’s shoulder, bemoaning his win streak. And then he starts tipping forward.
“Whoa—” Katsuki steadies him, palm flat against his ass. Kirishima clutches his shoulders. “Careful, dumbass, how much did you drink?”
Kirishima doesn’t say anything.
He’s wearing basketball shorts. They’re smooth, slippery under Katsuki’s hand. He’d needed to grab them, a little, to keep Kirishima upright, and it had pulled the fabric taut. Katsuki’s fingertips graze the center seam of them, cutting right through Kirishima’s slit.
Kirishima lets out a shaky breath.
His hips jerk.
Poor baby. The seam must be right over his clit.
The red flush on his face—Katsuki wonders if it’s all to do with alcohol, or if just a little bit of it comes from sensitivity. From embarrassment.
“Bakugou,” Kirishima whines quietly. It’s private, just in Katsuki’s ear.
Everyone else is eating, drinking, dancing. Kirishima, with his desperate little secret and unsteady breath, is just for Katsuki.
“What?” Katsuki asks. Feigns nonchalance. They’re just sitting beside each other. Kirishima is the one overreacting.
“Bakugou,” Kirishima says. His voice breaks. “C’mon.”
Katsuki wraps the fabric in his hand. The seam pulls tighter. Kirishima lets out a broken little noise and curls up into Bakugou’s side.
“Hey,” Katsuki says. “Drink water.”
“Wait, no—”
Kirishima pouts as Katsuki sits up and grabs an unopened bottle of water.
“I’m not that drunk,” he grumbles.
Katsuki knows. Kirishima likes pretending, so he can have plausible deniability for the shit he puts Katsuki through.
“Just drink.”
Kirishima, the piece of shit that he is, seems determined to pout over Katsuki no longer touching him, so it’s on Katsuki to tip the water bottle against his mouth. Some of the water dribbles down his chin. Wets his shirt.
“Asshole,” Kirishima mumbles. “Now I gotta change.”
“Right now?”
Kirishima just shoves him away and stands up. Katsuki watches him to make sure he doesn’t stumble—but he was right, before, he really isn’t that drunk.
He watches Kirishima walk out the front door.
Gives it a couple minutes before he follows him.
Katsuki had assumed, after U.A., that everyone had had enough of living with each other for three years, and would find their own way.
He guessed wrong. Half of them have collected in the same building. Hagakure and Ashido live on the tenth floor, Shinsou and Jirou on the twelfth, and Sero and Kaminari live across the hall from Katsuki and Kirishima’s shared apartment on the eighteenth.
This makes it easy enough for Kirishima to head up to their home. Katsuki wouldn’t have let him otherwise, high-functioning drunk or not.
He unlocks the door to their apartment.
It’s quiet inside. Kirishima hasn’t tripped over himself in the bathroom again, at least.
Katsuki walks down the hall, towards the bedrooms, and he hears it, then. A steady, wet shlick-shlick. Rushed, uneven breathing.
Poor, desperate baby.
Katsuki slips in the door. Just leans against the wall, hands in his pockets, and enjoys the view.
Kirishima’s shoulders are shaking, pressed deep into the mattress. His face is turned to the side, though, so Katsuki gets to hear the needy little noises that spill out of him like water from a fountain as he works a thick toy into his ass.
Sweat drips down his ass, outlining the muscle where the light hits it. His thighs shake, trembling with exhaustion. His pussy peeks out from behind his wrist, swollen and neglected.
He looks like a wet dream. Katsuki suddenly, strikingly, understands religion. Knows he could go to a church and outdo any priest with his devotion.
“Ba-ku-gou,” Kirishima whines.
Katsuki blinks.
But Kirishima’s not looking at him. His eyes are screwed shut, eyebrows scrunched together. He looks like he’s in pain.
Oh.
He’s fantasizing.
“Need you,” Kirishima mumbles, all to himself, sobbing as the toy pushes at his rim. “Hhng, can’t—” The widest part of the toy is just outside. He’s got a white-knuckled grip on the base, but it refuses to go in. Maybe it’s the angle. Maybe he’s so needy, so preoccupied with the Katsuki in his head, that it’s made him weak.
It’s okay. Katsuki’s here. He can help him.
Kirishima yelps when he sets his hand on the base of the toy, twisting to try and see him.
Katsuki shushes him, his free hand sparking at the small of Kirishima’s back.
“Just me,” he murmurs. “I’m helping you, relax.”
“You—you heard—”
“You called me,” Katsuki says. “So I came to help you.”
“I—Katsuki-i—nngh—”
The toy goes in with a wet, lewd noise, lube dripping down the sides of it and down onto Katsuki’s wrist.
Kirishima wails.
Katsuki thinks he could come just from the sight of him.
Kirishima’s body trembling from the strain of his toy, pussy dripping from how good his hole feels. There’s a wet little puddle on the sheets, and if Katsuki was any more distracted, he’d press his tongue to the cotton, drink it down.
But he has a job to do.
“Hey,” he says, patting Kirishima’s ass. “C’mon, turn over. Wanna do something.”
“Huh?”
Kirishima’s cock-drunk, barely listening—but he manages, turning over onto his back, and spreading his pretty thighs or Katsuki without even asking.
And Katsuki—
Katsuki almost tips forward, a mockery of Kirishima earlier, drunk off ten beers. It’s just—Kirishima’s pussy is tiny.
He’s so big everywhere else. His plush chest, thick arms, the faint lines of his abs, padded over with fat, the vast expanse of his thighs—his pussy, in comparison to all of it, is so pink, and soft, and little .
“Baby,” Katsuki mumbles. “You’re so pretty here.”
“Y—yeah?”
“Yeah. Fuck.” Katsuki moves closer, pulled by some magnetic force, like a sailor under the lure of a siren’s call. “Tiny little pussy. Been teasing me this whole time.”
“When did I—”
“Your gym shorts,” Katsuki says, through gritted teeth. “Are. See through.”
“...Oh. No kidding.”
“Don’t sound so smug.”
He looks up. Kirishima’s got a crooked smirk on his pretty face.
“It’s just—honestly, man, you kept looking at me, but you wouldn’t do anything. Wanted to see how much the great Dynamight could handle before he… y’know.” His thighs spread open another inch. “Snapped.”
“Manipulative fuck.”
“What’re you gonna do about it?”
He still looks smug, even with his hole stretched around a toy and his swollen pussy twitching every time Katsuki so much as speaks. Maybe he thinks he’s in control here. That Katsuki’s so degenerate that he’s going to give in and fuck him, after everything he’s done.
Katsuki’s never been big into playing with his food, but he thinks he’ll make an exception tonight.
“Wait, where are you going—”
“I wanted to try something,” Katsuki says, ignoring his upset whines. “You know, when you do those stretches at the gym, and you spread your legs, act all slutty—” There it is, in the first drawer of Kirishima’s desk. “Your shorts only save you a little.”
“What are you—” Kirishima sees what he’s holding, and his eyes go wide. “Wait, wait —”
Katsuki tears a short strip of tape off with his teeth.
“What’re you gonna do about it,” he mocks, pinning one of Kirishima’s thighs beneath his knee.
Kirishima’s pussy is soft to the touch. Katsuki feels him inhale—his abs go taut, live-wire tremor beneath the skin—but Katsuki doesn't do more than tape one chubby lip back. Bites off another strip of tape. Does the same to the other side.
Kirishima lets out a little whimper. “Katsuki.”
He wants him to touch. He’s dripping with how much he wants it—trying to coax Katsuki in with how wet he is.
But Katsuki has spent countless days watching him bend over in those tight little gym shorts. Salivated about the swell of his little pussy, squished between his thighs.
There’s nothing in his way, now, and he wants to watch.
“This is me snapping,” he says, standing back up. Pulls up a chair, and watches the confused look on Kirishima’s face melt into abject mortification.
“You’re just gonna—leave me like this?”
“You were busy when I came in,” Katsuki says. “I interrupted you. Get back to it.”
“But—” Kirishima makes a quiet, pathetic noise. “This isn’t— fair, c’mon, I said I was sorry, I—I’ll throw out the fucking shorts, okay, I’ll—I’ll—”
“You can do whatever you want after this,” Katsuki says calmly. Sits back. Relaxes. “C’mon. Show me what I wanna see.”
Kirishima shuffles up onto his knees, wincing as the toy moves inside him. His pussy is so pretty taped open like this. Baring his pink insides, his twitching hole, for Katsuki’s pleasure.
He’s not looking at Katsuki, though. His lips press together in a pout.
“I saved it for you,” he says petulantly. “That’s why I—put the toy in my—yeah. I thought you’d wanna stretch it out yourself.”
“How thoughtful,” Katsuki coos. “I’ll do that later, promise. Fuck you until we gotta wring out the sheets. But I wanna watch you first.”
Kirishima exhales. His eyes flick over to Katsuki, then, just as quickly, back away.
He begins to move.
Katsuki almost moans at the way Kirishima’s thighs flex as he bounces on his toy. It’s obscene—that sheer strength evident in the muscle, used for something so lewd. Kirishima sounds like he knows it, too, how obscene he looks—he makes these low, breathy noises like he’s doing something illegal, and trying to enjoy it before it kills him.
It might kill Katsuki. His mouth is dry. He swallows and it hurts. Wets his lips, tries to—sound normal, when he asks Kirishima, “How does it feel?”
“G—ood,” Kirishima breathes, eyes hazy and half-lidded. “Feels—really good, but my—I gotta—Katsuki, please, I can’t—”
Katsuki sees the problem.
Kirshima’s pussy is frothing over with slick. It’s almost a steady little stream of translucent, shiny liquid—dribbling down between his thighs and over the black silicone of the toy.
It needs something inside. Kirishima must be feeling it, that want, clawing inside of him. The hysterical kind of hunger.
“Please touch me,” Kirishima begs, eyes wide, imploring him. “Please, please, need you, Katsuki, it hurts—” He breaks off, panting as he raises himself off the toy again, thighs quivering—and crashes back down, keening.
His chest heaves from the impact. If Katsuki had attached bells to his nipple piercings, they’d be ringing.
Kirishima reaches for his clit, one shaking hand brushing the wet mound of his pussy. His eyes are closed, face tilted to the ceiling—he probably doesn’t even notice. Is just trying to feel better.
Katsuki clicks his tongue. Plays at police officer. “Hands above your head. No blocking my view.”
Kirishima does it without question. He’s not even fighting anymore. Just doing whatever Katsuki wants, because he thinks it’ll get his pussy filled faster.
Katsuki smiles, just a little—but it disappears, then, because Kirishima’s looking up at him, from beneath his tear-beaded lashes—and it’s—he’s—
“Gorgeous,” Katsuki breathes. “Hey, pretty boy. Look at you.”
Kirishima sniffles. “My legs hurt.”
“Brace yourself on your arms,” Katsuki says.
Kirishima looks happy, for a second, to be given a break—and then squints at Katsuki, betrayed, when he realizes the new position opens his hips up and pushes his pelvis out—baring his pretty pussy to Katsuki that much more.
His thighs twitch—like he almost brings them in, almost closes them—but Katsuki sees the reminder spark in his eyes. Katsuki wants to watch. Katsuki wants him like this.
Good boy.
Their game is almost over. Katsuki is growing impatient too. Wants to touch him, kiss him, treasure him—play with his tiny little pussy, press sweet kisses to his clit and savour the taste of it. Make him moan. Make him say thank you.
“C’mon, baby,” hes says quietly—and maybe Kirishima can hear it, the waning threat—because he nods, hiccuping, and fucks himself down onto the toy, back arching, pretty chest pressed out—
“Wait,” Katsuki says, laser-focused. “Stay there.”
The toy, pressed up at this angle, makes his pussy bulge. And it’s exactly what Katsuki thought it would be—makes his little pussy look so chubby, so swollen, that Katsuki almost comes in his pants.
“Katsuki!” Kirishima keens. “‘S— ‘s not enough, I need—”
“What is it, huh?”
“Touch me!”
His eyes go bright when Katsuki actually stands up and approaches the foot of the bed, and he scoots back to make room for him.
Kirishima’s cute, like this, surrounded by soft pillows. Katsuki wants to take a picture.
Kirishima spreads his thighs.
Katsuki can take one later.
He slots between Kirishima’s thighs. Pulls him up by the hips. The toy is pushed so deep that only the base is visible—and the bright orange X painted across it.
“Cute toy,” Katsuki says.
Kirishima flushes. “I—I wanted—”
“Yeah?”
“I want the real thing, Katsuki, come on, please—oh—”
Katsuki presses the flat of his thumb to Kirishima’s stiff little clit. It pulses against his finger, red-hot and needy.
“Hungry little pussy,” he murmurs, petting it. “How long were you gonna hide this from me, huh?”
“I wasn’t—”
“Say you’re sorry,” Katsuki says, moving back up to his clit. He pinches it, digs just a bit of his nail in, and grins when Kirishima whimpers in pain, hips squirming in a pathetic attempt to get away from him.
“I—But I didn’t mean to—” And he squeals as Katsuki’s open palm lands on his pussy.
“Apologize,” Katsuki says calmly. “C’mon, baby. Be good.”
“I—I’m so—” He makes the most adorable, high-pitched noise when Katsuki slaps him again, hand two sizes too big for his little pussy, and a million times too harsh.
“—rry,” Kirishima finishes miserably. “Sorry for teasing. I won’t anymore.”
“‘s okay. Pretty slut like you probably didn’t even notice, huh? Just wanted to show it off.”
“No, that’s not—”
Katsuki slaps him again. It lands right on his clit.
Having his pussy taped open like this, unable to protect itself—it’s one of the smartest things Katsuki’s ever thought of. He wonders if Kirishima would be open to just walking around like this. Letting his clit rub up against his jeans, driving him to oversensitivity until he collapsed into Katsuki’s lap, sniffling, begging for him to touch him. Katsuki wonders how desperate he’d have to be to ask for it in front of other people.
He slaps him just one more time, revelling in how soaked his hand is. Kirishima, for all his crying and moaning and squirming, loves this. He has to. Strings of white truth collect between Katsuki’s fingers.
“Shh,” he soothes, patting his pussy gently. Kirishima flinches away from the touch, like even that small, soft pressure is too much for his swollen pussy, turned the colour of a bitten-open cherry.
“I—I’m sorry,” he sobs. “I’m sorry for being so slutty, I—I just—needed you, wanted you to touch my—and I—I didn’t wanna make fun of you, I just—I wanted you, Katsuki.” He looks up at Katsuki with his big, watery cat-eyes.
So earnest, even like this. Katsuki adores him.
“Okay,” he says simply.
Kirishima blinks. “Oh…kay?”
Katsuki leans down. Drops a quick, sweet kiss to his mouth. “Yeah,” he says. “Want you. Done waiting. Gonna fuck you now, baby. Make my pretty slut feel good.”
Kirishima makes a happy little noise and tilts his face up. “Kiss me again,” he says, eyes closed. “And then the other thing.”
Katsuki laughs, and listens.