Katsuki grumbled as he stepped into his one bedroom apartment, three bags hanging off his arm as he closed the door, locking it behind him. His ruby eyes scanned the space for his pet, eyebrow quirked in confusion when he didn't see the bunny. "Oh well," The blonde sighed, kicking off his shoes and letting the grocery bags fall to the ground, fingers carding through his own hair as he plopped down onto the loveseat, eyes closed as he laid his head in his hand. His opposite hand reached down to fish his phone out of his hoodie pocket, lazily unlocking the device and opening Twitter, crossing his legs into an Indian style and furrowing his brows whilst he scrolled through his feed. After a few minutes, he got bored, tossing his phone onto the other end of the couch. "Izuku? Where are you?" He called for his pet hybrid, every part of him craving the touch from the little Omega, as his day at work had been stressful. That's the reason he had originally adopted the tiny hybrid, his therapist suggested investing in getting himself a service pet for his anger issues, and with no other option, he did. The night before, he had finalized the adoption of the male bunny, finally bringing him to his apartment so that he could see his new home. Izuku had been abused by his previous owners, so he tried his best to be gentle with the greenette, though the curly haired male understood that he had an issue with his temper, and tended to lash out easily.

The Omega had realized that he wasn't trying to hurt him after their first meeting, and that was just the Alphas' fiery personality, he wasn't lashing out at him. Soon enough, after their second meeting, the hybrid always got excited whenever he got to see the blonde, someone was actually interested in adopting him, after all. Katsuki remembered when he had went to pick him up, the bunny bounded to him happily, his little cotton ball tail was wagging, and his lop ears were straight up, a cheery smile present on his chubby face. The Alpha found it hilarious and adorable when they got back to his apartment and the rabbit binkied around for hours, only calming down when the spiky haired male called him for bed. He was wary at first, unsure if he was allowed in the bed, as his past owner hadn't let him on any of the furniture, but the taller male wasn't having it. He had to practically drag Izuku into bed. He loved his hybrid, even if he had only had him for two days. When the greenette never showed his face after waiting a few moments, he stood, burying his hands into his pockets, and walking to his small bedroom. "Deku?" He asked, peeking his head into the room, only to see his pet curled up in the corner, crying and whimpering next to a broken lamp. "Hey, Deku, are you okay?" He spoke as softly as he could, stalking over to him and crouching down, hesitantly reaching a hand out.

Izuku flinched, tears pouring down his freckled cheeks as he tried to scramble away from the man, before realizing he was cornered. "A-Alpha — Master, I'm so sorry!! I didn't mean to break i-it!" The younger male cried, eyes red and swollen. "I- I understand if you don't want me a-anymore! Or wanna hurt m-me..." His voice quieted, slowly moving so that he was on his stomach submissively. "I'm sorry, sir..."

"Hey, hey! Calm down, you're not in trouble, okay?" He said, backing up a foot or so.

The rabbit sniffled, "I'm not...?" He asked, glancing up at the man reluctantly.

"No.... You're fine, that lamp was trash anyways," He snorted, offering his hand again, the freckled boy taking it and letting himself be pulled up, sighing softly as he was embraced. "I'm not mad at you, okay? And don't call me 'Alpha' or 'Master', it makes me feel weird," He shuddered, sitting on the bed with the greenette seated in his lap, playing with his ears gently.

"Then.... What about..... Kacchan..?" He asked hopefully, gazing up innocently.

"I... Sure," The blonde chuckled lowly, holding the bunny close as he calmed him down. "I'm going to go make dinner, alright? Just clean up the mess you made," Katsuki's tone was gentle, petting his head softly as he got up. "You want broccoli?" Izuku nodded happily, his tail wagging faster than he'd ever seen before. With a low laugh, he walked into the kitchen.

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The blonde tediously chopped the carrots on the cutting board, Izuku watching in awe as he crept into the room, ears perked and his little nose twitching curiously. Katsuki turned around, the bunny hybrid hiding under the table as the male grabbed a pack of ramen out of a grocery bag next to the door, tilting his head as he followed his movements. The Alpha started to hum softly, before crouching down, staring at the green haired boy with an amused smirk. "You're not sneaky, you know?" The freckled male blushed, covering his face with his hands, thumping his foot once as he hopped out of hiding, pouting as he pulled out a chair to sit at the table. His owner continued to cook, his green orbs locked on his back whilst the older man steamed the broccoli that was meant to be his dinner, ramen and eggs cooking on the burner opposite to the pot. "So, what'd you do while I was at work?" The Alpha hummed, stirring the food mindlessly.

"Just slept, mostly.." He whispered. He didn't speak much, but when he did, he was very quiet, due to years of abuse. It was a miracle he could speak at all, most hybrids shut down and die after experiences such as that, but Katsuki was glad his little bunny prevailed. He didn't know what he'd do without him. Even at their first meeting, it did wonders for the stress that had been building up during the years, what with being a hero and all. The calming Omegan scent that rolled off the sweet hybrid was irresistible, and the man found an instant connection when he had met him. "What happened at work today, Kacchan?"

"Uh, well, got in a fight with a low level villain. The fucker didn't even know how to fight, he was using his quirk carelessly, almost crushed a kid to death.." The male spoke, looking behind him with a small grin, wanting to chuckle at the way the boy's eyes sparked with curiosity.

"What was his quirk?" The Alpha could tell he was intrigued with talking about his work. He'd learned that he was enamored with hero's over time, and he was still nervous around him because of it, due to the fact that he was the number two hero in Japan. The bunny had questioned why he lived in such a small apartment, even though it was still in a nice part of town, and asked why he wouldn't buy something bigger, considering his large salary. He'd told the hybrid that he has always lived alone when he graduated from U.A, and didn't see the need to have a large home, since it was just home. He was planning on investing in an actual house, to give the bunny room to live happily, instead of this cramped apartment.

"Just some telekinesis shit," He mumbled, setting a plate full of veggies down in front of the doe eyed rabbit. "Eat up," He said gruffly, sitting down across from him, a bowl of steaming ramen seated in front of him. Izuku looked down at his plate, mouth salivating at the assortment of fresh fruits and vegetables. That must've been what he had bought, then, he thought. The bunny dig in, nibbling and chewing on the carrots, his mouth full as he munched on the food that was given to him. "How do you feel about going to the park for your birthday?" He asked, obviously catching the boy off guard, as he coughed and choked on a leaf, spitting it out.

"My... my what?" He questioned, wiping his mouth with a napkin. The blondes' eyes narrowed.

"Your birthday. It's tomorrow, right?" He received a nod, the human taking a bite of food. "I wanted to do something special for you, since you've never technically celebrated it."

"Okay..." The male flushed red, finishing off his plate of food and running back to the bedroom. The spiky haired hero watched in confusion, shrugging his shoulders and continuing what he was doing.

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By twelve, Katsuki begrudgingly made his way to his room, head hung low as he struggled to stay awake. He tossed his tank top to the floor right outside his bedroom, slotting his slender fingers through his blonde spikes, hand landing on the doorknob. He hummed confusedly as he found he couldn't turn it, sighing in irritation. "Izu? Can you unlock the door, please?" He heard rustling inside, his ears perked as he listened closely.

"I.... I don't think that's... a good idea, Kacchan.." The timid voice of his pet spoke from behind the door. Katsuki growled lowly, mostly from sleepiness, and banged his hand against the door loudly.

"C'mon, bunny, I'm tired... Let me in so that I can sleep.." He sighed, leaning against the door frame, eyes closed as he inhaled sharply. Something felt.... off... He shook his head, letting a grin tug at his lips as the lock clicked. His large hand wrapped around the handle, pulling the door open and stepping inside the dimly lit room. Katsuki halted as he was hit with a wave of a sickly sweet smell, the scent filling his senses and making his knees week, his mind getting hazy and his eyes dilating. "I-Izuku..." The blonde muttered, softly closing the door and stalking over to the hunched over form on the bed, surrounded by his blankets and clothes, the hybrid sensually grinding his leaking cock down against the bed, moaning and sobbing in frustration as he couldn't get any relief. "Fuck, I.... Are you..."

"A-alpha.... it hurts... hurts so bad... what's happening t-to me..? Kacchan, Alpha, please help me..." He wailed, his hips bucking rapidly to hump the bed in search of any form of pleasure.

"God — Izuku, you're in heat?! What the fuck!? I can't- Damnit... You smell so fucking good.." The Alpha growled deeply, watching intensely as the Omega lifted his tail, slick drenched hole on display for the man as he presented, chest heaving as he pressed it to the makeshift nest, ass pushed upwards despite the shakiness in his limbs.

"Please...." The tiny male pleaded desperately, eyes half lidded and face red as he gazed over his shoulder, looking at the man expectantly, wiggling his hips as he pushed back further, neck tilted submissively to the powerful Alpha right behind him. "N-need... need you... need y-your cock, please... N-need it so, so badly...." The pro's breath hitched in his throat, eyes focused on the bunny's soaked entrance, slick running down his perfect, thick thighs in thick glops, the clear substance making his mouth water and his cock twitch in interest. The male sniffed the air, Izuku's arousal scent heavy in the room, a bulge obvious in the confines of his sweatpants. "I.... I want you, Katsuki. I have since I met you... I thought you knew... but... I'm only turning eighteen....It's my first heat.." He cried into the sheets, reaching a hand back to rub at his entrance, fingers sinking into his own heat, moaning out at the intrusion and unfamiliar sensation.

"Izuku, we can't... I'm fuckin' thirty.... The age gap is.. But I don't want to make things awkward between us, and —" Izuku howled loudly, cutting the man off as he painted, fingering himself seductively, biting down hard on his pink lips, green ears hanging by his head.

"I.... I've always wanted you... since the moment you made your debut..." The rabbit hybrid shuddered, gasping as he pressed against his own prostate, body shaking as he came all over his torso and the clothes underneath. "I.... I want your pups.... Even if some still refer to it as taboo, it's legal, isn't it..?" Izuku spoke with a teary smile, fingers still knuckles deep in his own ass.

Katsuki stood still, dick painfully hard in his sweats, claiming fangs completely elongated and claws out as he tried to decide whether to get out of the room, or to mate the little Omegan hybrid. He was offering himself to the man, and he couldn't help but to want to run his fingers through that soft fur, or bite on those long ears and pull that cute cotton tail of his. What if he got him pregnant? Would they be hybrids, or humans? Hybrids were just modified version of humans, their DNA mixed with animal genetics in order to give them animal-like qualities. Green fur covered most of the bunny's legs and waist, his feet like paws, but his hands considerably human like. The top half of his body was mostly human, save for his nose, whiskers and the lop ears on his head. They could speak, and perform like regular people could, so they could go to work and school, but they weren't allowed to live alone, so that's why the government had invented the hybrid adoption institution. Due to the fact that hybrids were still able to be Omegas and Alphas, they legalized Human/Hybrid relationships, though not everyone accepted this. Katsuki knew mating with the bunny could damper how the public saw him, he was close to being number one, after all, yet he couldn't deny the undeniable need to claim the boy, to have him hanging off his knot and to have his fangs buried in his scent glands.

"A-alpha...." The Omega whined, breaking the man out of his momentary trance, crimson orbs now focused intently on the trembling rabbit, an animalistic glint in his eyes. Izuku felt like he could melt, the blonde was staring at him like he was a full course meal getting served on a silver platter, and he was a starved man in which hadn't eaten in years. The musky scent of his arousal had his mind clouded, hands gripping his nest harshly, knuckles turning white as he once again wiggled his hips enticingly. "Please.." Was all he whispered in a final attempt in getting the man to come forth, laying his forehead against the plush materials below him with a long sigh, hole clenching in desperation with the need to be filled fully by the man, to be stretched by Katsuki's knot. The blonde was at a loss for words, his mouth felt dry as his lips formed into a thin line, eyes casted down at the bulge in his sweats. What was he supposed to do in this situation? None of the hybrid caretaking guides had ever specified what to do when a service hybrid went into heat like this, how was he supposed to react? His heart rate sped up, hands flexing with the craving to reach out and grab onto the little Omega sprawled out over his queen sized mattress, imagining his hands wrapped his teeny tiny waist as he pummeled his cock deep within him.

He couldn't stop the throaty growl that erupted throughout the small room, fangs sinking into his bottom lip painfully. Fuck it.. Katsuki groaned softly as he finally let himself grip onto the hybrid's plush thighs, smirking at the way the bunny's breath hitched in his throat, fingers edging closer to his leaking entrance bit by bit, before eventually dipping into the warmth. "God.... You're just sucking my fingers in so much..." The Alpha groaned, getting onto his knees on the bed, one hand swooping down to pull his pants down just enough for his throbbing dick to pop out, slapping against the greenette's ass cheek loudly. The blonde grinned at the soft moans, slowly pumping his length as he fingered the Omega, feeling how wet his insides were, just waiting for him, like even his body knew he belonged to the pro hero wholly. "Deku~" The older male cooed deeply in his ear, warm breath wafting over the milky skin and making a shiver wrack through his frail body.

"A-Alpha..." Izuku struggles to speak, what with those deliciously thick finger filling his hole and sating the aching in his stomach. He rolled his hips to angle his digits to hit his prostate, letting out a long, pleasure-filled howl, his legs quivering with the threat of giving out underneath himself as he felt the head of Katsuki's cock press against his entrance, the male removing his fingers from inside of him and slowly finding his hips, hands slightly squeezing at his waist.

"Tell me how bad you need it," The blonde snarled, fangs running over his bare neck while his bulbous tip pressed into the boy the smallest bit, but just enough to have the bunny's hands grip the sheets impossibly harder, his lop ears hiding his burning red face in embarrassment. "Fuckin' beg if you want my cock," The Alpha smirked, hand finding his tail and gripping harshly, eyes widening in shock at the loud, drawn out moan that escaped the hybrid's pink lips. "Damn, are all rabbits that sensitive there —" He pulled at his cotton tail again, eyes narrowing as he pressed into him a bit more. "Or is mine just a lil' slut?" The spiky haired hero chuckled at the high pitched keen, examining his fluffy tail to make sure he didn't actually hurt him, and had his other hand still wrapped around his waist.

"Kacchan — Alpha..... please..!" Izuku sobbed out, trying to get the man to press into him fully by angling his hips, though it didn't work. "I-I'll be a good Omega! J-just let me p-prove it.... I m-may be y-young and inexperienced... But —" The pro slapped his ass cheek, earning a little gasp, crimson eyes gleaming as he stared down at the red hand print left on the freckled flesh.

"Be quiet," The larger male grumbled, pulling his shirt off over his head. "You wanted this —" The man paused, forcing the bunny to turn around so that he was laying on his back instead, legs spread apart for the blonde. "So fucking take it!" Katsuki didn't care about the shrill that sounded throughout the bedroom as he slammed in ruthlessly, an evil grin tugging at his lips, the only thing he could focus on being the way the hybrid clamped down around him, green eyes sealed shut with the way he stretched his pink hole open. Slick gushed out from around his cock, letting his quirk go off against his side a bit, not enough to harm him, but just enough for effect. Izuku panted, squirming in the man's grip, nearly screaming as the blonde started a rough pace, hips bucking rapidly and shoving his length deep inside the poor boy, balls slapping against his backside as he slammed in and out of him.

"P-please—!!" Izuku yelped as he came viciously, thick ropes of white cum shooting onto his own torso as Karsuki continued fucking into him. "W-want your knot so bad! Kacchan, please!" Izuku moaned out, long ears laying limp against the bed as his hands found his broad shoulders, nails digging into the sun kissed skin on the man's back.

"Damn," The Alpha laughed, sweat dribbling down his forehead as he rammed his hips harder, gleaming at the echoing keens he let out as he hit his prostate, speeding up his pace. "You really are inexperienced, you came that fucking fast," He snorted, leaning down to kiss and suck on his swollen scent glands, before ramming in one last time, teeth sinking into the tender flesh as his knot formed completely. The warm liquid filled Izuku's insides, hole clenching and trying to suck him in, his rim stretching farther than before with the newly formed knot. "Get fucking pregnant, Omega," The blonde growled, listening to the rabbits' rapid heart rate, his breath rigid as he struggled to keep himself composed.

"I.... I love you, Kacchan..." Izuku mumbled, scarred fingers tangling in blonde locks, eyes drooping as he let his head fall back. "Thank you so much... I'll try my best to please you from now, Alpha..." The hybrid whined softly, eyes finally closing. He peeked one open as he felt soft lips ghost over his own, before he was engaging in the gentle, love-filled kiss, letting those strong arms wrap around him. He didn't flinch as Katsuki sat up, pulling the greenette with him, and just kept kissing his new mate.

"You really are just a stupid Deku, then," The older man chuckled, watching Izuku pout. "I love you, too, okay? You don't have to try to be good for me, you already fucking are."

The service hybrid quirked a brow in confusion, "I— What?" He asked, gasping as Katsuki ground up into him, wanting to squeeze his legs together to stop the strange feeling of his cum squelching around inside of him, but unable to do so in their current position.

"Don't worry about it," The blonde sighed, glancing down at the bed. "Damn, we made a mess..." He grumbled, reaching for his phone. "Get some rest, cotton tail. You'll need it," The bunny blushed, hiding his face in his chest as he closed his eyes once again.

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Kinda half assed, and very late, but you know- I didn't edit, so please don't point out mistakes lol. Stay healthy and beautiful my little pups!! Byeeeeeeeeee!!!🖤🖤🖤

Sorry for any spelling or grammar mistakes

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P.s. Happy Birthday, Deku!