The water drains with a low, hollow gurgle. Katsuki lifts Izuku from the tub, the boy’s body limp and dripping, and wraps him in a thick, black towel. He carries him from the steam of the bathroom into the cool, sharp air of the penthouse bedroom. City light cuts in through floor-to-ceiling windows, painting a grid of cold white across a vast platform bed made up with dark silk.

Katsuki lays him down in the center of it. The sheets are cool and slippery under Izuku’s back. He shivers, clutching the towel around his shoulders, his wide green eyes tracking Katsuki as the hero climbs onto the mattress, his weight making the frame groan.

“You’re trembling,” Katsuki says, his voice a low rumble. He kneels over Izuku, caging him in. “Cold? Or scared?”

“I… I don’t know,” Izuku whispers. It’s the truth. His skin is pebbled with goosebumps, but his heart is hammering, and a low, unfamiliar ache is pulsing between his legs. “It’s… a lot.”

“It’s supposed to be.” Katsuki’s calloused thumb brushes a stray curl from Izuku’s forehead. The gesture is almost tender. “You’re doing good. My devoted little fan. And we’re just getting started.”

Izuku’s breath hitches. “Started?”

“I have so much more to teach you.” Katsuki’s crimson eyes hold his, unblinking. “You want to learn, don’t you?”

Izuku nods, a frantic little motion. “Yes. Please. I… I want to know everything.” The words tumble out, earnest and terrified. He’s with his hero. His hero is teaching him. Making his body sing in ways he never imagined. The confusion is still there, a knot in his stomach, but it’s tangled up with something else now—a desperate, hungry curiosity. He doesn’t want this night to end.

Katsuki’s mouth curves, not quite a smile. “Good boy.” He shifts back, sitting on his heels between Izuku’s splayed legs. He pushes the towel aside, leaving Izuku exposed on the silk. Then he takes himself in hand, his thick, uncut cock already fully hard and leaking. It looks massive in the low light, a heavy, veined weight. “Look.”

Izuku looks. He can’t look away. Katsuki lays his cock against Izuku’s lower belly. The heat of it is a brand. The tip reaches past his navel; the thick base rests heavily against his tiny, hairless pussy. The sheer size of it, the impossible scale, makes Izuku’s mind go blank for a second.

“See that?” Katsuki’s voice is thick with pride. “That’s how deep I’m going into you. This…” He presses down slightly, the girth making Izuku’s soft belly dip. “This is gonna rearrange your guts, kid. You’re so fucking small. I’m gonna have to fuck it into you. All the way.”

Izuku whimpers, a high, thin sound. His hips give a tiny, involuntary jerk. The blunt head of Katsuki’s cock drags against his clit. A spark of sharp pleasure shoots through him, and his pussy clenches, empty and aching.

“All the way,” Katsuki repeats, leaning forward, his shadow swallowing Izuku whole. His breath is hot on Izuku’s ear. “Past that little entrance. Past that tight, hungry cunt. I’m gonna push right through your cervix. Into your womb. I’m gonna womb-fuck you, Izuku. Fill you up so deep you’ll taste me in your throat.”

Izuku’s small hand darts down, his fingers wrapping clumsily around the base of Katsuki’s cock. It’s hot and heavy, the skin like velvet over steel. He tugs, a weak, pleading pull, and bucks his hips up, grinding his sopping wet pussy against the thick length. A high, broken moan tears from his throat. “I want it,” he gasps, his green eyes wide and glazed. “Please, Dynamight… I want everything. Teach me everything.”

Katsuki groans, a deep, ragged sound that vibrates through Izuku’s entire body. He grinds down, his heavy balls and the thick shaft dragging through the slick mess between Izuku’s thighs. The friction is maddening—not enough, too much, perfect. “Fuck,” Katsuki pants, his breath coming hard. “Look at you. Dripping for it. Your little cunt’s begging.”

“It… it feels…” Izuku doesn’t have the words. He arches his back, chasing the pressure, his free hand fisting in the silk sheets. Every drag sends sparks through his nerves, a confusing cocktail of terror and blinding need.

“I know how it feels,” Katsuki rasps. He’s still moving, a slow, deliberate roll of his hips that smears pre-come and arousal across Izuku’s stomach and pussy. “But I can’t just shove this in you, kid. You’re too damn tight. Gotta open you up first.”

Yet he makes no move to stop. His cockhead catches on Izuku’s swollen clit, and Izuku cries out, his whole body seizing. Katsuki watches his face, captivated. “Gotta finger you open. Stretch that tiny hole for me. You understand?”

Izuku nods frantically, tears leaking from the corners of his eyes. “Yes. Yes, I understand. Do it. Please.”

“Ask nicer.”

“Please… please finger me open. I need… I need you to.” The words are a sob. His hips won’t stop moving, tiny, desperate circles against Katsuki’s weight.

"Keep begging," Katsuki growls, his hips still moving in that slow, torturous grind. His heavy balls slap wetly against Izuku's ass with each forward push. "Tell Dynamight everything you want. In detail, my little boy slut."

Izuku's mind whites out. The command cuts through the haze of sensation, a direct line to the part of him that still worships. "I want…" he gasps, his voice cracking. "I want your… your willy inside my kitty. Please."

Katsuki’s rhythm stutters. A dark, genuine laugh rumbles from his chest. "My willy," he repeats, the words dripping with amused possession. "Fuck, you aren't used to those new words yet, are you?” He leans down, his lips brushing the shell of Izuku's ear. "Say it right. Say 'cock'. Say you want my cock in your pussy."

"C-Cock," Izuku whimpers, the crude word feeling foreign and hot on his tongue. "I want your cock in my pussy. I want it to go all the way, like you said. I want to feel it… rearranging me." The confession sends a fresh flood of wetness between his legs, making the slide of Katsuki against him even slicker.

"Good. More." Katsuki nips at his earlobe. "What else?"

"I want…" Izuku's hands scramble up Katsuki's scarred back, feeling the powerful muscles working beneath his skin. "I want you to fill me up. So deep. I want to feel full of you. I want…" He sobs, the need a physical ache in his throat. "I want to be a good fan for you. Your best fan. Please, just… use me. Teach me how to take it."

Katsuki groans, a raw, approving sound. He grinds down harder, the thick ridge of his cockhead catching on Izuku's swollen clit with deliberate, circling pressure. Izuku shrieks, his back bowing off the bed. "You're learning so fast," Katsuki pants against his neck. "Your little cunt is dripping all over my balls. You taste that? That's how bad you want it."

"I taste it," Izuku cries, nonsensical, completely lost. He can smell it—the musky, salty scent of their mixed arousal hanging in the cool air. He's bucking his hips in frantic little circles, trying to get more friction, more pressure, more of that blinding spark. "I want it, Dynamight, I want it so much it hurts."

"It's gonna hurt," Katsuki promises, his voice guttural. He finally stills his hips, the sudden absence of motion a worse torture. Izuku whines, chasing the feeling. "Shhh. I know. But first, I open you up." He shifts his weight, kneeling back between Izuku's trembling thighs. "Watch."

Izuku lifts his head, his curls sticking to his damp forehead. He watches, breath held, as Katsuki spits into his own palm, then brings his thick, calloused fingers down to Izuku's exposed pussy. The first touch is a shock—cool, rough. Katsuki spreads the slickness there, his thumb rubbing slow, firm circles over Izuku's clit. Izuku jolts, a broken cry tearing loose.

"This is where you're greedy," Katsuki murmurs, his eyes locked on his own work. His index finger traces the soaked, puffy lips, then presses gently at the tight, hidden entrance. "This little hole. It's sucking at my finger already. Begging for it." He pushes, just the tip of his finger, and Izuku's world narrows to that single point of impossible, stretching pressure. It burns. It's too much. He tries to clamp his thighs shut on instinct, but Katsuki's knees are there, holding him wide open.

"Breathe," Katsuki orders, his voice low and steady. "Breathe through it. Let it in."

Izuku obeys, a ragged gasp filling his lungs. He focuses on the command, on the hero's voice, and as he exhales, the resistance gives. Katsuki's finger sinks in to the first knuckle. The burn melts, transforming into a deep, shocking fullness. Izuku's eyes roll back. "Oh…"

"There you go," Katsuki praises. He begins to move, a slow, shallow fuck with his finger, his thumb still working Izuku's clit in time. "See? Made for it. You're taking me so good." He crooks his finger, searching, and brushes a spot inside that makes Izuku see stars. A gush of wetness follows, soaking Katsuki's hand and the sheets beneath them. "Fuck, yes. There it is. Your body knows what it needs."

He adds a second finger alongside the first. The stretch is sharper, breathtaking. Izuku claws at the sheets, his mouth open in a silent scream. It's too much. It's everything. He's splitting open on Katsuki's hand, and the pleasure is a live wire, erasing every coherent thought except one: more. He needs more. He needs all of it.

Izuku’s hands scramble down his own trembling thighs, past his knees. He hooks his fingers behind his knees and pulls, his back arching off the silk, his legs folding open until his heels are near his ears. The position exposes him completely, his tiny, soaked pussy offered up, his hole fluttering around Katsuki’s two thick fingers. “K-Kacchan,” he gasps, the childhood name slipping out in a breathless plea. “More. Please, it feels… it feels so good.”

Katsuki’s crimson eyes blaze, fixed on the obscene display. “Look at you,” he breathes, his voice hushed with something like reverence. “A perfect little slut. Begging for it.” He curls his fingers inside Izuku, pressing hard against that spongy, electric spot. Izuku screams, his body convulsing, a fresh gush of slickness coating Katsuki’s wrist.

“Even when it hurts,” Izuku sobs, his hips rocking helplessly onto the invading fingers, “it still feels good. I don’t understand… but it does. Please, Kacchan, more. I need more.”

“You need it harder,” Katsuki growls, his own control fraying. He spits into his palm again, the sound crude and wet. He brings his slicked fingers back, pressing a third thick digit against Izuku’s stretched, quivering entrance. “You need to be ruined.” He pushes.

The burn is breathtaking. Izuku’s mouth opens in a silent scream, his knuckles white where he grips his own legs. He feels himself splitting open, the impossible fullness stealing the air from his lungs. Then Katsuki starts to move, a hard, piston-like rhythm, all three fingers fucking deep into him, the heel of his palm grinding against his clit with every thrust.

“There!” Izuku shrieks, his vision blurring. “Right there, please, don’t stop!”

Katsuki doesn’t. He sets a brutal pace, his fingers slamming into that perfect spot over and over, the wet, slapping sound filthy in the quiet room. He watches, mesmerized, as Izuku comes completely apart beneath him. “That’s it. Give it to me. Soak me, you desperate whore.”

Izuku’s orgasm hits him like a seizure. It isn’t a peak—it’s a dam breaking. A violent, pulsing gush of clear fluid erupts from him, drenching Katsuki’s hand, his own stomach, the sheets beneath them with a sound like pouring rain. He screams, his back bowing impossibly high.

Katsuki doesn’t let up. He keeps finger-fucking him through the convulsions, rubbing relentlessly at that spot, and the squirting doesn’t stop. It becomes a continuous, helpless flood, wave after wave of it, each thrust wringing another heavy gush from Izuku’s tiny, overwhelmed body. The scent of it, musky and sweet, fills the air.

“Fuck,” Katsuki pants, his own cock throbbing against his stomach, dripping pre-come onto the mess. “Look at you go. A fucking fountain. You’re squirting all over your hero, you filthy fanboy. You like that? You like making this mess for me?”

Izuku can’t speak. He can only nod, his body wracked by endless, mindless pulses. He’s sobbing, tears mixing with the sweat on his temples, his grip on his legs going slack. The pleasure is so intense it borders on pain, a white-hot wire of sensation that just keeps burning. He’s never felt anything like it. He never knew his body could do this.

Finally, after what feels like an eternity, the torrent slows to a trickle. Izuku collapses back onto the bed, boneless and gasping, his legs falling open in a limp sprawl. He’s trembling violently, every nerve alight. Katsuki slowly withdraws his fingers, the movement dragging another weak shudder from Izuku’s spent body.

Katsuki brings his soaked hand to his own mouth, his eyes locked on Izuku’s glazed ones. He licks his palm, his fingers, cleaning them with deliberate, obscene slowness. “Tastes like your devotion,” he rasps. Then he leans over Izuku, bracing his hands on either side of the boy’s head. His massive, leaking cock rests heavily on Izuku’s slick, quivering stomach.

“You’re open now,” Katsuki rasps, his cock a heavy, searing weight on Izuku’s stomach. “But you’re not ready. Not for this.” He grinds down, the thick shaft leaving a wet trail of pre-come on Izuku’s skin. “Gonna need your mouth first. Get me nice and slick with your drool. Otherwise, I’ll tear you in half.”

Izuku’s breath hitches. His gaze drops from Katsuki’s burning eyes to the monstrous cock resting on him. It’s thicker than his wrist. The purple head is beaded with moisture, the foreskin pulled back just enough to show the glistening slit. It looks impossible. “My… mouth?”

“That’s right.” Katsuki shifts his weight, kneeling up. He wraps a fist around his own base, giving his length a slow, deliberate stroke. The sight is obscene. “Think my number one fan can deep throat all eleven inches? Get this monster cock nice and wet for your greedy little cunt?”

Izuku whimpers. The crude question, the sheer size of him, should be terrifying. But the ache between his own legs is a dull, persistent throb. His spent pussy clenches around nothing. He wants to be good. He wants to be used. “I… I’ll try,” he whispers.

“You’ll do more than try.” Katsuki’s voice leaves no room for failure. He moves, his hands hooking under Izuku’s arms, hauling the smaller boy up the silk sheets until his head is level with Katsuki’s hips. “Open.”

Izuku obeys, his mouth falling open. Katsuki doesn’t guide himself in gently. He taps the broad, leaking head against Izuku’s lips, smearing pre-come across them. The taste is salty, musky, overwhelmingly male. “Lick it,” Katsuki orders, his voice a low growl. “Get it wet. Show me how much you want it.”

Trembling, Izuku extends his tongue. He laps tentatively at the slit, collecting the bitter fluid. The texture is smooth, hot. He swirls his tongue around the crown, and Katsuki lets out a sharp, approving hiss.

“Good boy. Now suck.”

Izuku takes the head into his mouth. It’s too big. It stretches his lips wide, pressing against the roof of his mouth. He gags immediately, his eyes watering.

“Breathe through your nose,” Katsuki instructs, his hand coming to cradle the back of Izuku’s head. Not gentle. A claim. “Relax your throat. You want it, remember? You begged for it.” He applies pressure, pushing forward another inch.

Izuku gags again, tears spilling down his freckled cheeks. He forces himself to inhale, the air whistling through his nostrils. The cock in his mouth is a solid, unyielding heat. He can feel every vein, every pulse. He tries to suck, his tongue flattening against the underside.

“That’s it,” Katsuki murmurs, watching him with rapt intensity. “Take it. You’re making a mess.” Drool is already dripping from Izuku’s stretched lips, coating Katsuki’s shaft. “Deeper.”

He pushes again. Izuku feels the head bump against the back of his throat. His body seizes, a primal reflex to reject the invasion. Katsuki holds him there, his grip firm. “Swallow,” he commands.

Izuku tries. His throat works convulsively around the intrusion, and suddenly, it gives. The head pops past the ring of muscle. Katsuki groans, a deep, visceral sound of pleasure. “Fuck. There.” He feeds Izuku another inch, then another, until half his length is buried in the boy’s throat.

Izuku can’t breathe. His vision spots. He claws weakly at Katsuki’s thighs, a silent plea.

Katsuki pulls back, just enough to let him gasp a ragged breath. “Again,” he says, and pushes back in, faster this time. He sets a rhythm, shallow thrusts that fuck Izuku’s mouth, each one going a little deeper. The wet, choking sounds are filthy. Spit and pre-come slick the entire length of him now, shining in the low light.

“Look at you,” Katsuki pants, his hips moving with more insistence. “My devoted little fanboy. Choking on your hero’s cock. You dream about this?” He thrusts deeper, and Izuku’s nose presses into the coarse blonde hair at his base. “You dream about swallowing your Dynamight’s dick whole?”

Izuku can’t answer. He can only take it. His jaw aches. His throat is raw. But a strange, submissive pride blooms in his chest. He’s doing it. He’s pleasing him. His own hips squirm against the sheets, his soaked pussy aching for attention.

Katsuki seems to read his mind. He pulls out completely, his cock glistening with spit. Izuku coughs, dragging in air, his lips swollen and bruised. “Not bad,” Katsuki says, his voice rough with arousal. He strokes himself, spreading the slickness. “But I need more.”

“On your back,” Katsuki commands, his voice gravel-rough. He stands up off the bed, his shadow engulfing Izuku. “Head off the side. I’m gonna fuck that throat pussy full before I move onto your tiny cunt.”

Izuku scrambles to obey, his body weak and trembling. He shifts until his shoulders are on the mattress, his head hanging back into empty air. The city lights swim in his upside-down vision. He feels exposed, vulnerable, his throat offered up.

Katsuki steps to the edge of the bed, his heavy cock bobbing, slick with spit. He grips the base, aligning the broad head with Izuku’s gaping, swollen lips. “Open wider, fanboy.”

Izuku does, a soft whimper escaping him. Katsuki doesn’t hesitate. He pushes in, not with the controlled pace from before, but with a single, relentless thrust. The thick crown pops past Izuku’s lips, rams against the back of his throat, and keeps going.

Izuku gags, a wet, choked sound. Tears spring to his eyes instantly. Katsuki’s length sinks deeper, stretching his esophagus, a solid, burning heat that feels like it’s reaching into his chest. He can’t breathe.

“Swallow,” Katsuki grunts, his hands coming down to frame Izuku’s face, thumbs pressing into his jaw. He pulls back an inch, then shoves forward again, deeper. “Swallow around it. Make it good for me.”

Izuku tries. His throat works convulsively, muscles fluttering around the invading girth. The sensation makes Katsuki groan. “Yeah. Just like that. Taking it like a good little slut.”

He sets a rhythm, shallow at first, then deepening with each thrust. The wet, slapping sounds of his hips meeting Izuku’s face are obscenely loud. Spit drips from the corners of Izuku’s mouth, runs down his temples into his hair. He claws at the sheets, his body arching.

“You feel that?” Katsuki pants, driving in to the hilt. Izuku’s nose is buried in coarse blonde hairs on his balls, the heavy scent of musk and sweat filling his senses. “That’s all eleven inches. Your hero’s dick, buried in your throat. You dreamed of this, didn’t you?”

Izuku can’t answer. He can only take it, his body vibrating with the force of the thrusts. A strange, dark pleasure coils in his gut. He’s being used. Completely. The ache between his own legs returns, a throbbing, empty need.

Katsuki’s pace turns brutal, his control slipping. He fucks Izuku’s face in earnest, his hips pistoning. “Gonna come down this pretty throat,” he snarls. “Gonna fill your stomach with it. That what you want?”

Izuku manages a weak, gurgling moan. His consent is a given. His body is a vessel. Katsuki’s thrusts become erratic, his grip on Izuku’s face tightening. With a final, deep grind, he stills, and Izuku feels the hot, pulsing release flood the back of his throat.

He swallows reflexively, again and again, the bitter taste overwhelming. Katsuki holds himself there, groaning through the last waves, before slowly pulling out. Izuku coughs, gasping for air, come and spit slick on his chin.

Katsuki looks down at him, his chest heaving. He swipes a thumb through the mess on Izuku’s face, then pushes it into his mouth. “That’s my good little fanboy.”

Izuku suckles weakly at the thumb, his eyes glazed and submissive. The taste is salt, bitterness, and victory.