Katsuki’s hand slides from Izuku’s belly to his hip, a slow, possessive drag. The fire pops. The silence is thick, but it’s not quiet. It’s full of their breathing, the wetness between Izuku’s thighs, the promise hanging in the dry, pine-scented heat.

“You good?” Katsuki’s voice is a low rumble against his temple.

Izuku nods, his cheek rubbing against Katsuki’s chest. He feels raw. Open. Loved so completely it aches in his bones. “Yeah.”

“Good.” Katsuki shifts, rolling Izuku onto his back. The blankets fall away. The cold air hits Izuku’s damp skin, and he shivers. Katsuki looms over him, his crimson eyes dark, reflecting the firelight. He braces himself on one arm, his other hand coming to cradle Izuku’s jaw. “Because we’re not done.”

Izuku’s breath hitches. “We’re not?”

“No.” Katsuki’s thumb strokes his cheekbone. “I’m gonna fuck you everywhere in this place. That means every inch of it.” His gaze sweeps the cabin—the rug before the hearth, the wooden table, the kitchen counter, the frost-rimmed window. “I’m gonna fuck you everywhere, Izuku. Until this whole cabin smells like us. Until you can’t walk without feeling me.”

A violent, liquid thrill shoots through Izuku’s core. His pussy clenches, empty and aching. “Daddy…”

“That’s right.” Katsuki kisses him, deep and claiming. When he pulls back, his lips are wet. “Gonna fill you so full you’ll look pregnant by morning. You want that?”

Izuku’s head is spinning. He can only nod, frantic. “Yes. Please.”

“Then get up.”

Katsuki stands, his body a silhouette of muscle against the fire. He’s already hard again, his thick cock jutting out, flushed and heavy. He offers a hand.

Izuku takes it, letting his father pull him to his feet. His legs are shaky. He stumbles, and Katsuki catches him, steadying him with a firm grip on his waist.

“First,” Katsuki says, his voice dropping to a rough whisper near his ear. “Right here.”

He turns Izuku to face the window, the black night and the silent, falling snow beyond the glass. Izuku’s own reflection stares back—wide green eyes, flushed skin, messy green hair. Katsuki’s reflection appears behind him, larger, encompassing.

“Watch,” Katsuki commands, his hands on Izuku’s hips.

He doesn’t bend Izuku over. He pulls him back, flush against his chest, and Izuku feels the blunt, hot head of his cock nudge against his slick entrance from behind. Izuku gasps, his hands flying to the cold windowpane. The contrast is shocking—ice against his palms, fire where his father pushes inside.

“Fuck,” Katsuki grunts, sinking in with one slow, relentless thrust.

Izuku cries out, his forehead pressing against the glass. He’s still loose and wet from before, but he’s sensitive, every inch of his inner walls singing as Katsuki fills him. He watches, mesmerized, as his father’s reflection buries itself in him, as his own mouth falls open in a silent moan that fogs the window.

Katsuki sets a brutal, deep rhythm, fucking into him with sharp, driving snaps of his hips. The window rattles softly with each impact. Izuku’s fingers scramble for purchase on the smooth glass.

“See that?” Katsuki pants, his eyes locked on their reflection. His hands are tight on Izuku’s hips, sure to leave bruises. “See who you belong to?”

“Y-you,” Izuku chokes out, his vision blurring. The pleasure is a tight coil in his gut, winding faster with every thrust. “Daddy, I’m—I’m gonna—”

“Come.”

It’s not a suggestion. It’s an order. Izuku shatters, a raw scream tearing from his throat as his orgasm rips through him. He feels it—the gush of fluid, hot and uncontrollable, soaking his thighs and splattering against the wooden floorboards between their feet. His knees buckle.

Katsuki holds him up, fucking him through the convulsions, his pace never faltering. “Good. That’s one.”

He doesn’t stop. He fucks Izuku right through the oversensitivity, until Izuku is sobbing, begging for a mercy that isn’t coming. Only when Katsuki’s own rhythm stutters does he still, burying himself to the hilt with a guttural groan. Izuku feels the hot, pulsing flood of his father’s release inside him, another thick load joining the first, making his already-full belly feel impossibly heavier.

Katsuki stays there for a long moment, his forehead against Izuku’s shoulder, both of them panting against the cold window. Then he pulls out slowly.

The sound is obscenely wet. Izuku sags, but Katsuki’s arm bands around his waist, holding him.

“Look down,” Katsuki murmurs.

Izuku does. A stream of white, mixed with his own clear slick, is already dripping down his inner thigh. His stomach, soft and rounded, is visibly distended.

“See?” Katsuki’s hand splays over the slight swell, pressing gently. Izuku whimpers. “Told you.”

He turns Izuku around and kisses him, deep and filthy. Then he breaks the kiss, his eyes blazing. “Next.”

He leads a dazed Izuku to the heavy wooden dining table. He doesn’t bother clearing it; he just lifts Izuku and sets him on the edge, the rough grain cold against his ass. Izuku leans back on his elbows, his body on display in the firelight.

Katsuki steps between his spread thighs. He looks down at the mess he’s made—Izuku’s used, dripping cunt, his swollen belly. He wraps a hand around his own cock, which is still half-hard and gleaming with their mixed release. He gives himself a few rough strokes, smearing it all over his length.

“You’re making a mess, kid,” he says, but his voice is thick with pride.

“You’re the one—” Izuku starts, but his protest dies in a gasp as Katsuki pushes back inside him in one smooth, deep thrust. The angle is different, deeper, hitting a spot that makes Izuku see stars.

This time, Katsuki fucks him with a steady, grinding pace, leaning over him, his hands braced on the table on either side of Izuku’s head. He watches Izuku’s face, studying every twitch, every gasp.

“You take me so good,” Katsuki growls. “My perfect boy. My son.”

The words, so wrong and so right, send another jolt of pure heat through Izuku. He wraps his legs around Katsuki’s waist, pulling him closer, taking him deeper. “More, Daddy, please, more—”

Katsuki obeys. His thrusts become harder, faster. The table scrapes against the floor with each drive. A forgotten mug clatters to the floor and shatters. Neither of them notice.

Izuku comes again with a broken cry, his back arching off the table. This one is a fountain, a squirting gush that soaks Katsuki’ lower abdomen and the table beneath them. Katsuki curses, his rhythm faltering, and then he’s coming too, another hot flood painting Izuku’s insides.

When he pulls out this time, the mess is catastrophic. Come drips from Izuku onto the table, pooling on the wood. It drips from Katsuki’s cock, thick and white, onto the rag rug below.

They don’t clean it. Katsuki just lifts Izuku off the table, carries him to the kitchen counter, and sets him down on the cold tile. The cycle repeats.

Against the cabinets. On the rug before the fire, where Katsuki eats him out until Izuku screams and squirts into his mouth, and Katsuki drinks it down before fucking him full again. In the narrow hallway, Izuku bent over, hands on the wall, Katsuki pounding into him so hard the framed pictures rattle.

Each round leaves its mark. A wet patch on the sofa. A sticky smear on the bathroom doorknob. The cabin grows warm, humid, saturated with the salt-musk scent of sex.

In the bathroom, Katsuki stands Izuku before the mirror over the sink. Izuku can barely stand. He’s trembling, his body glistening with sweat, his stomach rounded and taut with the sheer volume of seed inside him. His cunt is red, swollen, leaking a continuous, slow trickle of white down his thighs.

Katsuki stands behind him, his own body slick, his cock a monstrous, persistent thing, still hard, coated in a frothy, whitish glaze. He wraps a hand around Izuku’s throat, not squeezing, just holding. Possessing.

“Look at you,” Katsuki rasps, his eyes meeting Izuku’s in the glass. “Look what I did to you.”

Izuku stares at his reflection. He looks ruined. Claimed. His eyes are glazed, his lips kiss-swollen. He looks… pregnant. The thought is a lightning strike of taboo pleasure. A soft sob escapes him.

Katsuki kisses his shoulder. “You’re so beautiful like this. Full of me.” His free hand slides down Izuku’s belly, pressing. Izuku moans, feeling the pressure, the slosh of liquid deep inside. “Gonna keep you like this. Always.”

Katsuki lifts him, arms hooked under his knees, spreading him wide. Izuku’s back is flush against Katsuki’s chest, his body suspended, completely open. He’s forced to watch in the mirror as Katsuki pushes back inside.

The stretch is brutal, perfect. Izuku can see everything—the obscene glisten of his own pussy, the way Katsuki’s cock drives into him, fucking up a frothy, messy lather from the sheer force of it. It bubbles and spills, white and slick, with every punishing thrust.

The slide is wet, loud, obscene in the small room. Izuku is so full, so profoundly *his*, and he can’t look away from the ruin of it in the glass.

“Come on the mirror,” Katsuki grunts, his pace frantic now. “Mark it. Show everyone who comes here whose boy you are.”

Izuku’s climax hits him like a seizure. He screams, his body bowing, and a jet of clear fluid, mixed with white, shoots from him with force, splattering across the mirror in a streaky, opaque web. It drips down, distorting their reflections.

Katsuki shouts, his hips slamming home as he empties himself for what feels like the tenth time, his release so copious it overflows, dripping from Izuku’s stretched entrance onto the bathroom floor tiles with a soft *pat pat pat*.

He collapses forward, catching himself on the sink, his body heavy against Izuku’s back. They stay there, panting, staring at their ruined, blurred reflections in the cum-streaked glass.

Somehow, they make it to the bedroom. The loft is dark, the only light a pale grey hint of dawn seeping around the edges of the blinds. They don’t make it under the covers. They fall onto the rumpled sheets, a tangled heap of exhausted, sticky limbs.

Izuku’s head is on Katsuki’s chest. He can’t move. Every muscle is liquid. He feels hollowed out, stuffed full, branded. The smell of sex and sweat and his father is a blanket around him.

Katsuki’s arm is heavy around him, his hand resting once more on the slight, firm curve of Izuku’s belly.

“Daddy?” Izuku’s voice is a hoarse scrap of sound.

“Hm?”

Izuku shifts, his body a symphony of aches, and slides down the bed. He takes Katsuki’s softening cock into his mouth without a word. He sucks, hard, his tongue working the thick length, swallowing the bitter-salt taste of their mixed release. He deep-throats him, his nose pressing into the coarse hair at the base, and holds it there until his own throat convulses. He pulls off with a wet, gasping pop. Katsuki is fully hard again, pulsing against Izuku’s cheek.

“One more time, Daddy,” Izuku whispers, his voice shredded. “Please.”

He climbs, movements clumsy and saturated, and straddles Katsuki’s hips. He guides the fat head to his swollen, dripping entrance and sinks down in one slow, excruciating slide. A punched-out groan leaves them both. Izuku braces his hands on Katsuki’s chest and begins to move, riding him with a desperate, bouncing rhythm that makes his small, tender tits bounce wildly. He throws his head back, a show, an offering.

“Look at you,” Katsuki rasps, his hands coming up to grip Izuku’s hips, guiding the punishing pace. “Fucking yourself on me. My greedy boy.”

“Gonna—gonna make sure,” Izuku pants, each downward slam forcing a sharp cry from his throat. “Fill me one more time. Make sure I’m a mommy. Make sure I’m gonna have Daddy’s baby.”

“You will,” Katsuki growls, his hips surging up to meet him, driving deeper. “Gonna pump you so full it takes. You’ll swell up with it. Everyone’ll see.”

Izuku sobs, his rhythm fracturing into frantic, grinding circles. “Do it. Do it now, I can’t—I need it—”

Katsuki’s control snaps. He flips them, pinning Izuku to the mattress, and fucks into him with a final, brutal urgency. His release isn’t a flood this time—it’s a deep, pulsing ache, a last, claiming deposit forced into the deepest part of him. Izuku screams, his body bowing, and then he’s coming too, a geyser of clear fluid erupting from his overstimulated cunt, soaking Katsuki’s abdomen and the sheets beneath them in a hot, squirting wave.

Izuku collapses, boneless. Katsuki falls atop him, his weight a solid, anchoring heat. Izuku turns his head, finds Katsuki’s mouth in the near-dark, and gives him a sloppy, exhausted kiss. It tastes of salt and sweat and completion.

“Love you,” Izuku mumbles against his lips.

“Love you, kid,” Katsuki breathes back, the words a rough vibration between them.

They don’t move again. Sleep crashes over them like a physical weight, dragging them under in a tangle of limbs and the profound, sticky evidence of the night. The last thing Izuku feels is the heavy, possessive weight of Katsuki’s hand, once more splayed over the slight, firm curve of his belly.