Katsuki’s house, once a monument to sterile order, now hummed with a foreign warmth. Inko’s pastel sketches were taped to the stainless steel refrigerator. The scent of jasmine tea lingered in the air, a soft ghost over the clean lines of his modern kitchen. It had been three days since they’d moved in, and Katsuki clung to routine like a lifeline, rising at five to claim the home gym before anyone else stirred.

The clang of weights was his prayer. He was on his back, pressing a heavy barbell, muscles screaming, sweat pooling in the hollow of his throat. His focus was absolute, a wall against the thoughts that crept in during silence. The wedding was in a week. He could hold for a week.

The door to the gym whispered open.

“Oh. You’re up early, Kacchan.”

Katsuki’s arms locked, the weight suspended above his chest. Izuku stood in the doorway, bathed in the pale morning light from the hall. He wore only a pair of tiny, black satin shorts that clung to the curve of his ass and did nothing to hide the shape of him. His chest was bare, the smattering of freckles across his collarbones, the pink, puffy nipples pebbled in the cool air.

“Couldn’t sleep,” Izuku continued, his voice a sleep-rough murmur. He padded in, the sound of his bare feet on the rubber matting too loud. “Mind if I join you?”

Katsuki racked the bar with a deafening clatter. He sat up, grabbing his towel. “It’s five-thirty.”

“I see that.” Izuku smiled, stretching his arms overhead, his back arching. The shorts rode higher. “You’re all sweaty.”

“It’s a gym. That’s the point.” Katsuki wiped his face, avoiding the green eyes tracking him. He could feel the kid’s gaze like a physical touch, sliding over his bare torso, the damp waistband of his shorts. His own shorts, thank god, were loose, but he felt himself thickening traitorously, a slow, aching pulse of blood he willed to stop.

“You have a really nice body for an old guy,” Izuku said, tilting his head. He walked over to the dumbbell rack, his movements a languid, conscious display. He bent at the waist to pick up a light weight, giving Katsuki a full, uninterrupted view of the satin straining over his ass, the cleft clearly visible.

Katsuki’s mouth went dry. He stood up, turning toward the water cooler. “Don’t you have clothes?”

“It’s hot. And it’s my house now, too, right?” Izuku straightened, turning. He began a set of lazy curls, his biceps flexing. His eyes never left Katsuki. “Mom’s still asleep. She sleeps like the dead. Always has.”

“Don’t talk about your mother like that.”

“Why? It’s true.” Izuku put the weight down. He took a few steps closer, close enough for Katsuki to smell the clean scent of his skin, see the dew of sweat already forming in the hollow of his throat. “You’re all tense, Kacchan. You should relax. Big week ahead.”

“I am relaxed.”

“Your jaw is clenched so tight I’m surprised your teeth aren’t powder.” Izuku’s gaze drifted down, lingering blatantly at Katsuki’s groin. A slow, knowing smile spread across his freckled face. “See something you like?”

Katsuki felt a flush of pure heat crawl up his neck. He was hard, fully, shamefully hard, the fabric of his gym shorts tenting. There was no hiding it. The kid had seen it, was watching it with a predator’s focus. “Get out.”

“Or what?” Izuku whispered, taking another half-step. “You’ll tell Mom? What would you say?” He mimicked Katsuki’s gruff baritone poorly. “‘Inko, your son is distracting me with his…’ what, exactly? His existence? His shorts?” He laughed, low and soft. “She’d just say you were being silly. That her sweet boy was just trying to bond.”

Katsuki couldn’t move. He was trapped between the water cooler and Izuku’s advancing body, his own arousal a heavy, throbbing betrayal against his thigh. He wanted to shove him away. He wanted to pull him closer.

“You smell good,” Izuku murmured, his eyes half-lidded. “All that sweat. Salt and… you.” He inhaled, audibly. “It makes my head feel fuzzy.”

From down the hall, a door clicked open. Inko’s gentle voice floated toward them. “Katsuki? Are you in the gym? I thought I heard voices.”

Izuku didn’t jump back. He simply took a graceful step to the side, picking up a towel and draping it over his shoulder, his expression shifting seamlessly into one of innocent exertion. “Morning, Mom!” he called, cheerful. “Just getting a workout in with Kacchan.”

Inko appeared in the doorway, dressed in a soft robe, her green hair mussed from sleep. She smiled, warm and unaware. “My two early birds. I’ll start breakfast.” Her eyes swept over Katsuki, and her smile softened. “Oh, sweetheart, you’re drenched. Don’t overdo it.”

Katsuki could only nod, gripping the edge of the cooler, his knuckles white. He couldn’t straighten up. Not with the blatant, unforgiving ridge of his erection pressing against the damp fabric. He was pinned by it, by Inko’s kind eyes and Izuku’s hidden smirk.

“I’ll finish up in here,” Izuku said, his voice pure sweetness. “Kacchan looks like he needs a minute. Or ten.”

Inko nodded, drifting back toward the kitchen. Izuku waited until her footsteps faded. He didn’t look at Katsuki again. He just picked up his weight, resuming his curls, a faint, victorious smile playing on his lips as Katsuki stood frozen, aching and exposed, in the middle of the room he no longer controlled.

Izuku’s eyes didn’t leave the prominent bulge in Katsuki’s shorts. He bit his plump bottom lip, the gesture obscene. “It’s not going away, is it, Daddy?” he murmured, the title a hot brand in the quiet room. “Looks painful.”

Katsuki said nothing. He couldn’t. His breath was sawdust in his throat.

“I could help with that,” Izuku offered, his voice a conspiratorial whisper. He took a slow step closer, his gaze lifting to Katsuki’s face. “I wouldn’t mind. I’ve seen you looking.” His hands came up, fingertips brushing over his own small, pert chest. He pinched a pink nipple, rolling it deliberately. “You want to fuck my tits, don’t you? Bet they’d feel amazing around that big cock.”

The words were a physical strike. Katsuki flinched. “Stop.”

“Why? No one’s here.” Izuku’s fingers trailed down his own sternum, over the flat plane of his stomach, stopping at the waistband of his shorts. “Mom’s making breakfast. She’ll be busy for twenty minutes, at least. We have time.”

“There is no ‘we’.” Katsuki forced the words out, his voice gravel. He finally pushed off from the cooler, turning his body sideways in a pathetic attempt to hide his condition. The movement only made the fabric pull tighter.

Izuku laughed, a soft, breathy sound. “Liar.” He closed the final distance, standing so close Katsuki could feel the heat radiating from his bare skin. “Your body doesn’t lie, Kacchan. It’s screaming. It’s so hard it’s leaking, isn’t it?” His eyes were wide, feigning innocence. “I can see the wet spot.”

Katsuki looked down. A dark, damp patch had indeed bloomed on the gray fabric, right over the head of his cock. The evidence was undeniable. Humiliation burned through him, hotter than desire.

“Let me see it,” Izuku breathed. He didn’t wait for permission. His hand came up, fingertips ghosting over the strained fabric.

Katsuki caught his wrist. His grip was vise-tight, his own hand trembling. “Don’t.”

Izuku didn’t struggle. He just looked at the hand restraining him, then up into Katsuki’s eyes. His expression was open, curious. “You’re shaking. Are you scared of me? Or scared of how much you want it?”

“I don’t want it.”

“Your cock says otherwise.” Izuku’s free hand darted out, palming him roughly through the shorts.

Katsuki jerked, a choked gasp ripping from his throat. The contact was electric, a jolt of pure sensation that blurred his vision. Izuku’s hand was small, hot, and it squeezed, exploring his length through the fabric, thumb rubbing over the wet, sensitive tip.

“So thick,” Izuku whispered, awed. He leaned in, his lips brushing Katsuki’s ear. “I want to taste it. Just a lick. You can pretend it never happened.”

Katsuki’s resolve was a sandcastle against a tide. His hips bucked, pushing into that wicked little hand. A low, helpless groan escaped him.

“That’s it,” Izuku coaxed, his voice sweet as poison. He dropped to his knees.

The sight was devastating. Izuku on his knees, green curls messy, looking up through his lashes. His breath puffed hot against the damp fabric. He nuzzled the length of him, inhaling deeply. “God, you smell good. All mine.”

“Izuku—” Katsuki’s protest was a weak thread.

Izuku’s hands came up, squeezing his small, pert chest together, trapping the thick line of Katsuki’s cock between them. The damp fabric of the gym shorts was a rough, hot barrier as Izuku began to rub up and down, his hardened pink nipples dragging against the length. “We can leave your shorts on, if that makes you feel better, Daddy,” he breathed, his eyes locked on Katsuki’s face. “Do you like my tiny tits, Daddy?”

Katsuki’s head thumped back against the wall. A broken sound, half-groan, half-sob, tore from his throat. The pressure was exquisite, a maddening friction that made his hips jerk forward, seeking more. “Izuku… goddamn it.”

“That’s a yes,” Izuku whispered, a smile in his voice. He increased the pace, his breath coming faster, his own arousal evident in the flush spreading down his chest. “They’re so sensitive. I can feel every inch of you. So big. You’re gonna make me come just from this, Daddy.”

“Stop calling me that,” Katsuki gritted out, but his hands, of their own volition, came up to cradle Izuku’s head, his thumbs brushing the sharp line of his jaw.

“Why? It’s what you are.” Izuku tilted his head, nuzzling into the touch. “My mother’s husband. My new daddy.” He punctuated the title with a harder, rolling grind of his chest, his nipples pebbled tight against the fabric. “You like it. I can feel your cock twitching. It’s leaking so much for me.”

Katsuki was. The wet spot was spreading, the head of his cock a slick, aching pressure against Izuku’s sternum. The smell of his own precum mixed with Izuku’s clean sweat, a potent, shameful musk. His entire body was a live wire, his control incinerated.

Izuku’s tongue darted out, a hot, wet stripe against the damp fabric right over the swollen head of Katsuki’s cock. He moaned, low and genuine, as he tasted the salt-bitter seep of precum. “You taste so manly, Daddy,” he breathed, dazed, nuzzling the soaked spot. He sucked the fat tip through the shorts, the material pulling tight, his lips forming a seal.

Katsuki’s hips jerked. A ragged sound tore from his throat. His hands, still cradling Izuku’s head, tightened in the green curls, not pushing him away, but holding him there, a silent plea for more.

“Daddy’s really gonna make me cum by only rubbing his big fat cock against my tits,” Izuku whispered, his voice hazy with want. He sucked harder, his tongue working in firm circles, his own hips squirming against empty air. A damp patch was spreading on the front of his tiny shorts. “Fuck, I’m so wet. Just from this.”

“You’re… you’re disgusting,” Katsuki gritted out, but it was a weak, broken thing. His whole body was trembling, a fine, violent shake that started in his thighs and climbed up his spine.

Izuku pulled back, a string of saliva connecting his lips to the fabric. He looked wrecked, his cheeks flushed, his lips slick and parted. “You love it. You love how disgusting I am for you.”

Izuku rolled his little tongue around the wet, clothed tip, drooling on himself, the saliva dripping onto his small, pert tits. “Are you gonna cum for me? Are you gonna cum in your shorts and all over my tits, Daddy? I’m a bad dirty boy. Cover my tits in your cum.”

Katsuki’s hips stuttered forward, a helpless, jerking motion. His hands were fists in Izuku’s hair, holding him close, forcing the rhythm. “Shut up,” he rasped, but it was a plea, not an order.

“Make me.” Izuku’s voice was muffled against the fabric, hot and wet. He sucked harder, his cheeks hollowing, his own breath coming in ragged pants. The front of his tiny satin shorts was soaked through, a dark, blatant patch. “I’m so close. Just from this. Your cock’s gonna make me squirt all over the floor.”

The confession snapped something in Katsuki’s chest. A final, thin wire of restraint. A guttural sound ripped from his throat, raw and animal. His spine arched, his hips driving forward, grinding his swollen length against Izuku’s face and chest. The friction was maddening, the damp fabric a torturous barrier. “Fuck. Izuku—”

“That’s it, Daddy, give it to me,” Izuku chanted, his words slurring. He released his chest, letting his tits bounce free, and used both hands to knead Katsuki’s ass, pulling him deeper into the grind. “Cum. I want to feel it. I want to wear it.”

Katsuki cummed. It was a violent, shuddering wave that tore through him with blinding force. His vision whited out at the edges. Thick, hot pulses soaked through his shorts, the fabric going slick and warm as the release painted Izuku’s collarbones, his throat, the upper swell of his small breasts. Katsuki’s legs trembled, his weight sagging against the wall, held up only by Izuku’s grip and his own fading strength.

Izuku moaned, a high, desperate sound. He rubbed his face and chest into the mess, smearing it across his skin and freckles. His whole body convulsed, his back bowing, and a sudden gush of wetness darkened the satin at his crotch, a puddle spreading on the polished concrete floor beneath his knees. The sharp, sweet smell of his release mixed with the musk of Katsuki’s spend.

For a long moment, there was only the sound of their harsh, panting breaths. Katsuki’s head hung, his forehead pressed to the cool wall. Shame flooded in where heat had been, cold and sickening.

Izuku leaned back on his heels, looking down at himself. He dragged two fingers through the cum on his chest, brought them to his mouth, and sucked them clean. His eyes never left Katsuki’s face.

“You taste even better than I imagined, Daddy.”