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The autumn air carried the scent of change through Musutafu's streets, and Bakugo Katsuki breathed it in deeply as he walked toward the hero agency building. At twenty-two, he'd carved out a reputation as one of the most formidable pro heroes despite, or perhaps because of, his Omega status. The media loved their "Explosive Omega" headlines, though he'd blown up enough reporters' equipment to make them think twice about the phrasing.
His hair caught the late afternoon sunlight as he approached the gleaming tower of Endeavor's agency. Today marked the beginning of a joint operation between several agencies, something about coordinated villain activity that required multiple hero teams. Katsuki didn't particularly care about the details, he was just ready to blow something up.
The agency's lobby buzzed with activity. Heroes from various agencies mingled, their conversations a mix of strategy and casual catch-up. Katsuki's eyes swept the crowd, cataloging faces and threat levels out of habit. Then he froze.
Standing near the far wall, speaking earnestly with a cluster of heroes, was a man with dark green hair and a build that made Katsuki's breath catch. Broad shoulders tapered to a narrow waist, and even through the professional hero costume, Katsuki could see the definition of years of intense training. The man was tall, taller than Katsuki remembered, and when he gestured while speaking, the movement was confident and sure.
But it was the profile that made Katsuki's heart skip. The gentle slope of his nose, the determined set of his jaw, the way he tilted his head slightly when listening intently.
Izuku.
The name whispered through his mind like a prayer he'd forgotten he knew. Fifteen years. It had been fifteen years since their families had been torn apart, since he'd watched his best friend disappear from his life because of circumstances neither of them could control.
As if sensing his gaze, the man turned, and Katsuki found himself staring into familiar forest-green eyes. For a moment, time seemed suspended. Those eyes widened, and Katsuki watched recognition dawn across features that had matured from soft childhood curves into sharp, masculine lines.
"Kacchan?" The nickname fell from the man's lips in a whisper that somehow carried across the noisy lobby, and Katsuki felt something deep in his chest crack open.
The world seemed to blur at the edges as Midoriya Izuku began moving toward him. Other conversations faded to white noise. The distance between them felt both infinite and negligible.
Then they were standing face to face, close enough that Katsuki could see the small scar above Izuku's left eyebrow that hadn't been there in childhood, close enough to smell the warm, earthy scent that was so familiar it made his chest ache.
"Izuku," Katsuki breathed, and watched his childhood friend's face light up with that radiant smile that had been burned into his memory.
"You got tall," were the first words out of Izuku's mouth, followed immediately by a blush that spread across his cheeks. "I mean, not that you weren't always going to be tall, but you were shorter than me when we were kids and now—"
"You're babbling," Katsuki interrupted, but there was no heat in it. His voice was softer than it had been in years, rough with emotions he couldn't quite name.
Izuku's smile turned sheepish. "Some things don't change."
They stood there for a moment, drinking each other in. Katsuki noted how Izuku's hero costume hugged his frame, the confidence in his posture that spoke of someone who'd grown into his strength. This wasn't the uncertain boy who'd cried when they'd been separated. This was a man, a hero, someone who commanded respect.
"Midoriya!" A voice called out, breaking their bubble of reunion. "We need you for the briefing."
Izuku's eyes never left Katsuki's face. "Can we... after this is over, could we talk? Really talk?"
Katsuki nodded, not trusting his voice. As Izuku was pulled away by the operation’s demands, Katsuki caught his scent again, warm earth after rain, with something new underneath it. Something that made Katsuki's pulse quicken and his body respond in ways that had nothing to do with childhood friendship.
The briefing passed in a blur. Katsuki tried to focus on the villain intel, the strategic assignments, and the coordination protocols. But his eyes kept drifting to where Izuku sat three rows ahead, taking meticulous notes in that same concentrated way he'd done homework as a child. Except now, those shoulders were broader, and Katsuki found himself wondering what those hands would feel like—
He cut that thought off sharply. This was Izuku. His childhood best friend. He couldn't be thinking about him like that just because his Omega biology was responding to an Alpha's presence.
Except... it wasn't just any Alpha, was it?
The operation itself was straightforward. A coordinated strike on three villain hideouts suspected of being connected. Katsuki found himself paired with Izuku's team for the main location, and despite the years apart, they fell into sync almost immediately.
Izuku, once quirkless, had developed an amazing quirk. Even with his raw power, his movements where fluid and calculated, creating a style that was uniquely his. Analytical, adaptive, and absolutely devastating.
"Behind you!" Izuku called out, and Katsuki spun, letting off a perfectly timed explosion that sent three villains flying. In the same motion, Izuku was there, catching the one Katsuki's blast had missed with a controlled strike.
They moved like they'd been fighting together for years instead of meeting again for the first time that afternoon. It was unsettling and exhilarating and felt so *right* that Katsuki couldn't concentrate on anything else.
"Kacchan, pattern seven!" Izuku shouted over the chaos, and Katsuki's body responded before his mind caught up. They'd made up numbered patterns for their play fights as children, elaborate scenarios where they'd save the world together. That Izuku remembered, that he thought Katsuki would remember too...
Katsuki launched himself high, raining explosions down while Izuku swept low, their combined assault creating a pincer movement that had the remaining villains surrendering within minutes.
As the smoke cleared and the cleanup crews arrived, Katsuki found himself standing close to Izuku again. Too close, maybe, because that scent was stronger now, mixed with sweat and adrenaline and something that made Katsuki's mouth water.
"You remembered," he said quietly.
Izuku's smile was soft. "I remember everything about you, Kacchan."
The words hit him like a physical blow. Katsuki felt heat rise in his cheeks and had to look away before he did something stupid like close the distance between them.
"Coffee?" Izuku asked, his voice gentle. "I know a place that's quiet."
***
The café was tucked away from the main streets, the kind of place that catered to people who wanted to talk without being overheard. They sat in a corner booth, steaming mugs between them like a buffer against fifteen years of separation.
"I looked for you," were the first words out of Izuku's mouth. "When I got old enough to understand why we had to move, I tried to find you. But your family had moved too, and..."
"We moved to Kyoto when I was twelve," Katsuki said quietly. "Mom got a job offer she couldn't refuse. I tried to find you too."
They sat in silence for a moment, the weight of lost years heavy between them.
"Why did your parents really move you?" Katsuki asked. "I know they said it was because you presented early, but..."
Izuku's hands wrapped around his mug. "There were... concerns. About a quirkless, Alpha child having the potential to develop a powerful quirk. The local hero commission thought it would be better if I trained somewhere with more specialized facilities for Alpha children." He looked up, meeting Katsuki's eyes. "My parents didn't want to separate us, but they were scared. They thought it was what was best for everyone."
"And you presented when you were seven." It wasn't a question.
"Seven and three months," Izuku confirmed. "Early even by Alpha standards. You hadn't presented yet, and everyone thought..." He trailed off.
"Thought what?"
"That you'd be a Beta," Izuku said quietly. "The doctors said there was no indication you'd be anything else. My parents were worried about... influence. About an Alpha child affecting your development."
Katsuki felt a bitter laugh escape. "Joke's on them. I presented Omega at eleven."
Izuku's scent shifted, taking on a warmer note that made Katsuki's nerve endings sing. "I'm glad," he said softly.
"Glad I'm an Omega?" Katsuki bristled slightly.
"Glad you're you," Izuku corrected. "Whatever that means. I've followed your career, you know. You've redefined what it means to be an Omega hero. You've never let anyone put you in a box or tell you what you can't do."
The praise made something warm uncurl in Katsuki's chest. "You followed my career?"
"I have alerts set for any news about you," Izuku admitted, color rising in his cheeks. "I know that probably sounds creepy, but I just... I needed to know you were okay. That you were happy."
"Are you happy?" Katsuki found himself asking.
Izuku considered the question seriously. "I am now," he said finally. "Being a hero was everything I dreamed it would be. Helping people, making a difference... it's exactly what I wanted. But there was always something missing. Someone missing."
The air between them seemed to thicken. Katsuki could smell Izuku more clearly now—that warm earth scent was definitely Alpha, but there was something else. Something that called to a part of him he'd kept carefully locked away.
"Izuku," he started, then stopped. How could he explain the way his body was responding? The way every instinct was screaming that this was right, that this was home?
"I know," Izuku said softly. "I can smell it too."
Katsuki's eyes widened. "You can?"
"Kacchan, you smell like..." Izuku paused, seeming to search for words. "Like everything I've been looking for my whole life. Like compatibility. Like..." He took a shaky breath. "Like a mate."
The word hung between them, loaded with implications neither of them had been prepared for when they'd walked into that agency lobby.
"That's not possible," Katsuki said, but his voice lacked conviction. "We were kids. We would have known—"
"Didn't we?" Izuku leaned forward slightly. "Think about it, Kacchan. Really think. Do you remember how we used to gravitate toward each other? How we could never bear to be apart for long? How we always knew what the other was thinking?"
Katsuki did remember. He remembered the way they'd always ended up sitting close together, the way Izuku's presence had always calmed him, the way leaving had felt like tearing away part of his soul.
"Childhood bonds aren't the same as mate bonds," he said weakly.
"No," Izuku agreed. "But what if they were never childhood bonds? What if they were always mate bonds, just... dormant? Waiting for us to be old enough to understand?"
Katsuki stared at him, his mind reeling. Mate bonds were rare, especially fate bonds—the kind that existed before presentation, before conscious recognition. The kind that pulled souls together across time and distance.
"I never dated anyone seriously," he found himself admitting. "Never found anyone who... fit."
"Neither did I," Izuku said quietly. "I thought maybe it was because I was too focused on hero work, but..."
"But it was because they weren't you."
The confession slipped out before Katsuki could stop it. Izuku's eyes widened, and his scent shifted again, taking on a note that made Katsuki's breath catch.
"Kacchan," Izuku said, and his voice was rough with emotion. "Can I—would it be okay if I scented you? Just... just to be sure?"
Scenting was intimate, reserved for family and close friends at minimum, for lovers and mates at maximum. It was a request that should have made Katsuki defensive, should have triggered his need to maintain independence.
Instead, he found himself nodding.
Izuku moved slowly, telegraphing his intentions, sliding around the booth until he was sitting next to Katsuki instead of across from him. Up close, his scent was overwhelming—warm and safe and Alpha in a way that made Katsuki want to bare his throat.
"Is this okay?" Izuku asked, his hand hovering near Katsuki's shoulder.
"Yeah," Katsuki breathed.
Izuku's hand settled gently on his shoulder, thumb brushing against the scent gland at the base of his neck. The touch sent electricity through Katsuki's entire system, and he had to bite back a sound that was dangerously close to a purr.
Then Izuku leaned in, nose brushing against Katsuki's throat, and breathed in deeply before rubbing the scent blend on his wrist against Katsuki's neck.
The effect was immediate and overwhelming. Izuku's scent spiked, rich with Alpha pheromones that spoke of claiming and protection and mine. Katsuki felt his biology respond, felt the telltale loosening in his abdomen that meant his body was preparing for a heat that was still weeks away.
"Oh," Izuku breathed against his throat. "Oh, Kacchan."
"What?" Katsuki managed, his voice embarrassingly breathy.
"You're going into heat," Izuku said, pulling back to look at him with concern. "I can smell it. Your cycle's shifting."
Katsuki felt panic flutter in his chest. "That's not—I'm not due for another three weeks, and I'm on suppressants—"
"Mate bonds can trigger early heats," Izuku said gently. "Especially if the bond's been dormant for a long time. Your body is recognizing mine as a suitable mate and preparing accordingly."
The clinical explanation did nothing to help Katsuki's racing heart. "I can't go into heat. I have work, I have commitments—"
"Hey," Izuku's hands framed his face, thumbs stroking across his cheekbones. "It's okay. We'll figure it out. I'm not going anywhere, and I won't let anything happen to you."
The Alpha authority in his voice, the promise of protection, made something inside Katsuki settle even as his rational mind rebelled.
"I don't need you to protect me," he said, but there was no real heat in it.
"I know," Izuku said seriously. "You're the strongest person I've ever known, Omega or not. But that doesn't mean you have to handle this alone. Not if you don't want to."
Katsuki stared into those green eyes, searching for any sign of deception or manipulation. All he found was sincerity and a warmth that made his chest ache.
"What are you saying?"
"I'm saying that if this is a mate bond—if we're really fated to be together—then I want to try. I want to court you properly, get to know the man you've become. I want to be worthy of you."
The old-fashioned phrase 'court you' made Katsuki's heart skip. "You want to court me?"
"If you'll let me," Izuku said softly. "I know this is sudden, and we've just found each other again, but Kacchan... I've been in love with you since we were children. I just didn't have the words for it then."
The confession hit Katsuki like a physical blow. "Izuku..."
"You don't have to say anything," Izuku said quickly. "I know it's a lot, and I don't expect—"
"I love you too, you idiot," Katsuki interrupted. "Always have. Even when I was trying to convince myself it was just missing my friend."
The smile that spread across Izuku's face was radiant. "Really?"
"Really," Katsuki confirmed. "But if we're going to do this, we're going to do it right. Proper courtship, getting to know each other as adults, all of it. I'm not going to bond with someone just because my biology says I should."
"Of course," Izuku agreed readily. "Whatever you want, whatever you need. We have time."
Katsuki felt some of the tension leave his shoulders. "Good. Because I need to call my agency and let them know I'm going to be out of commission for a few days."
"Your heat?"
"My heat," Katsuki confirmed. "And before you offer, no, I don't need an Alpha to help me through it. I've been managing my heats alone for over a decade."
Izuku's expression was carefully neutral. "Of course. But... if you change your mind, if you need anything at all, call me. Promise?"
The concern in his voice, the way he was clearly holding back from offering more direct help, made Katsuki's chest warm. An Alpha who respected his autonomy even in the face of biological imperatives was rare.
"I promise," he said softly.
***
Katsuki's heat started thirty-six hours later, hitting him like a freight train while he was trying to clean his apartment. One moment he was folding laundry, the next he was doubled over as his body temperature spiked and slick began coating his inner thighs.
He barely made it to his nest before the first wave of need crashed over him.
It was different from his usual heats. More intense, more urgent, filled with an aching emptiness that his toys couldn't quite satisfy. His body was calling for something specific, someone specific, and every instinct was screaming ‘Alpha, need Alpha, need Izuku’.
By hour six, he was sobbing with frustration, slick-soaked and desperate. His skin felt like it was on fire, and the cramping in his abdomen was worse than anything he'd experienced before.
His phone buzzed with a text message.
Izuku: Just checking in. How are you feeling?
Katsuki stared at the screen through heat-glazed eyes. His hands shook as he typed back.
Katsuki: Fine
The response came almost immediately.
Izuku: Kacchan, I can smell your distress from three blocks away. Please let me help.
Three blocks away? Katsuki's rational mind filed that information away as concerning, but the rest of him focused on the offer of help. His biology was screaming at him to accept, to call his Alpha and beg him to come ease the burning need.
Katsuki: Just bring supplies. Nothing else.
Izuku: On my way
Twenty minutes later, Katsuki heard the key code being punched into his front door, followed by footsteps and the sound of bags being set down.
"Kacchan?" Izuku's voice carried down the hallway, carefully controlled but edged with concern. "I'm leaving supplies by your door. Food, electrolyte drinks, fresh blankets. Is there anything else you need?"
Katsuki tried to answer, but all that came out was a broken whine. The sound of Izuku's voice, the knowledge that he was so close, was making the heat symptoms worse.
"Kacchan? Are you okay?"
Katsuki could hear the worry in Izuku's voice, could smell his scent growing sharper with concern. Without conscious thought, he found himself crawling out of his nest and toward the bedroom door.
"Don't come in," he managed to say, his voice rough and desperate. "Just... don't leave either."
There was silence for a moment, then: "I won't leave. I'll stay right here, okay? As long as you need me to."
Katsuki pressed his back against the bedroom door, letting Izuku's scent wash over him. It wasn't enough, his body was still demanding more, demanding everything, but it took the edge off the desperation.
"Talk to me," he said.
"What about?"
"How about you start with how you unlocked my door?"
Izuku chuckled. "I called Kirishima on the way over and he gave it to me."
"Bastard. I'll have to thank him and then kill him later."
"Don't hurt your friend Kacchan." Izuku teased.
" He's used to it."
" Anything else you want to know?"
"Anything. Everything. What you've been doing for fifteen years."
So Izuku began. He talked about his training, about the first time he'd used his quirk without breaking his bones, which caused Katsuki to ask more questions. After Katsuki's curiosity was sated, Izuku continued talking about the friends he'd made and the people he'd saved. He talked about quiet moments and victories and failures, painting a picture of the man he'd become.
Katsuki listened, letting Izuku's voice anchor him through the worst of the heat waves. When the need became too much, he'd whine or make soft distressed sounds, and Izuku would immediately shift to softer tones, sometimes humming lullabies he remembered from childhood.
"I used to dream about you," Izuku admitted during one of the quieter moments. "Even before I understood what the dreams meant. I'd dream that we were together, that we were a team saving the world. I'd wake up with this aching sense of loss, like I'd forgotten something important."
"I had those dreams too," Katsuki whispered against the door. "Always woke up feeling empty."
"Not empty anymore?"
Katsuki considered the question. Even burning with heat, even desperate and slick-soaked and aching, there was a rightness to Izuku's presence that settled something deep in his chest.
"No," he said softly. "Not empty anymore."
The heat lasted three days. Three days of Izuku camping outside his bedroom door, providing food and comfort and endless conversation. Three days of learning about each other as adults, of rebuilding their connection word by word.
On the fourth morning, Katsuki woke clearheaded for the first time in days. His skin was no longer hypersensitive, the cramping had faded, and the desperate need for his Alpha’s attention had settled into something manageable.
He found Izuku asleep sitting against his door, head tilted back against the wood. Even in sleep, he looked ready to respond to any sign of distress.
"Izuku," Katsuki said softly.
Green eyes opened immediately, alert despite having clearly not slept well. "Kacchan? How are you feeling?"
"Better." Katsuki opened the door properly for the first time in three days. "Like myself again."
Izuku's eyes did a quick scan, checking for signs of lingering heat symptoms, before meeting his gaze. "Good. That's good."
"Thank you," Katsuki said simply. "For staying. For... everything."
"You don't need to thank me," Izuku said, climbing stiffly to his feet. "I told you I wasn't going anywhere."
They stood there for a moment, the air between them charged with new understanding. Katsuki had let Izuku take care of him in the most vulnerable state possible, and Izuku had done so without asking for anything in return.
"I need a shower," Katsuki said finally. "And food that isn't energy bars."
"I'll make breakfast," Izuku offered.
"You know how to cook?"
Izuku's smile was sheepish. "I learned. Figured it was an important adult skill."
As Katsuki headed for the bathroom, he paused in the doorway. "Izuku?"
"Yeah?"
"When I said I wanted proper courtship... I meant it. But maybe we could start with breakfast and see where it goes from there."
The smile that spread across Izuku's face was bright enough to power the city. "I'd like that. I'd like that a lot."
***
Six months later, Katsuki stood in the same agency lobby where they'd been reunited, but this time the tension in his shoulders had nothing to do with seeing Izuku again. They'd just completed another successful joint operation, their teamwork so seamless that other heroes had started requesting them specifically for difficult cases.
"The media's calling us the perfect Alpha-Omega partnership," Katsuki said as they walked toward the exit together.
"Do you mind?" Izuku asked, glancing at him with concern. "I know you hate being defined by your secondary gender."
"Normally I would," Katsuki admitted. "But they're not wrong, are they? We are perfect partners."
Izuku's scent warmed with pleasure. "Yeah, we are."
Their courtship had been everything Katsuki could have asked for. Izuku had been patient and attentive, taking time to learn Katsuki's preferences and boundaries as an adult. They'd gone on proper dates, spent hours talking about everything and nothing, rebuilt their friendship into something stronger and more mature.
The physical attraction had grown steadily alongside the emotional connection. Izuku's touches had become bolder, more confident. Kisses that started soft and sweet had begun to carry hints of heat and promise. Katsuki found himself thinking more and more about what it would be like to truly bond with his Alpha.
His Alpha. When had he started thinking of Izuku that way?
"Kacchan?" Izuku's voice pulled him from his thoughts. "You okay?"
"Yeah," Katsuki said, then paused. "Actually, no. I need to ask you something."
Izuku stopped walking, turning to face him with immediate attention. "What is it?"
Katsuki took a breath, gathering his courage. "My next heat is in two weeks."
"Okay," Izuku said carefully.
"I don't want to spend it alone this time."
Izuku's eyes widened, his scent spiking with interest and arousal before he carefully controlled it. "Are you sure? I don't want you to feel pressured just because—"
"I'm sure," Katsuki interrupted. "I want you there, Izuku. I want you with me."
"Just to help you through it?" Izuku's voice was carefully neutral. "Or..."
"I want you to bond with me," Katsuki said, the words coming out in a rush. "If—if you want to. I know it's permanent, and I know we haven't talked about it officially, but I love you and I want to be yours and I want you to be mine, and—"
Izuku silenced him by cupping his face in both hands, thumbs stroking across his cheekbones. "Yes."
"Yes?"
"Yes, I want to bond with you. Yes, I want to be yours. Yes to everything." Izuku's smile was radiant. "I've been waiting for you to be ready. I would have waited forever if that's what you needed."
Katsuki felt tears prick at his eyes. "I'm ready now."
"Then we'll bond during your heat," Izuku said softly. "I'll take care of you, and you'll be mine, and I'll be yours."
The promise sent shivers down Katsuki's spine. "All of that sounds perfect."
Izuku leaned down to press a soft kiss to his lips. "I love you, Kacchan."
"I love you too, Izuku."
***
Two weeks later, Katsuki woke to the familiar heat building in his core, but this time there was no panic, no desperate scramble to prepare for days of solitary suffering. This time, Izuku was there, had been there for three days preparing Katsuki's apartment, stocking the kitchen, washing and scenting blankets for the nest.
"How do you feel?" Izuku asked, appearing in the doorway with a glass of water and Katsuki's morning suppressants.
"Different," Katsuki admitted, accepting the glass. "Better. Ready."
Instead of taking the suppressants, he set them aside on the nightstand. Izuku's eyebrows rose.
"You're sure?"
"I'm sure."
Izuku nodded slowly, a small smile curving his lips. “Alright then.”
Katsuki set the glass of water down as Izuku moved to stand in between Katsuki's legs. Katsuki looked up at him, heart racing at the heat in his Alpha’s gaze
“You know what this means, right?” Izuku asked, voice low and rough. “If we do this, there’s no going back. You’re mine, forever.”
“I know,” Katsuki breathed, hands coming up to rest on Izuku’s thighs. “And you’re mine. I don’t want to be apart anymore.”
Izuku leaned down to capture Katsuki’s lips in a searing kiss, pouring all of his love and desire into it. Katsuki moaned, arching up into the press of Izuku’s body.
They took their time undressing each other, hands and mouths exploring every inch of scarred skin that mapped out their sacrifice.
Katsuki’s eyes widened as Izuku’s impressive cock sprang free from his boxers, thick and long and already leaking with need. He had a feeling Izuku was big but the sight of that huge, pulsing shaft made him lick his suddenly dry lips in hesitation.
“Holy shit, Izuku,” he breathed, reaching out a trembling hand to wrap around the hot, silky length. “You’re so fucking big.”
Izuku smirked, hips rolling forward into Katsuki’s grip. “All for you,” he purred. “Can’t wait to feel this pretty little mouth wrapped around me.”
Katsuki shuddered at the dirty words, giving Izuku’s cock a slow, experimental stroke. The heavy flesh pulsed in his palm, and he could feel it throbbing with each beat of his Alpha’s heart.
Emboldened by his Alpha’s low groan of pleasure, Katsuki leaned forward and licked a slow stripe up the underside of Izuku’s shaft, from base to tip. The salty-sweet taste of pre-cum exploded on his tongue, and he moaned at the flavor.
“That’s it,” Izuku encouraged, fingers threading through Katsuki’s hair. “Take it in your mouth. Show me how much you want it.”
Katsuki opened his mouth wide and took the swollen head between his lips, swirling his tongue around the sensitive flesh. He could only take a few inches at first, but he worked his way down steadily.
Izuku’s reactions were delicious, harsh pants and grunts of pleasure, the flex and roll of his hips as he struggled not to thrust too deep. Katsuki felt powerful, knowing he was the one driving his Alpha wild.
He bobbed his head faster, taking Izuku deeper with each pass, until his throat was fluttering around the thick intrusion. Tears pricked at the corners of his eyes from the intensity of it, but he didn’t stop, determined to make his Alpha come undone.
When Izuku’s cock pulsed and swelled against his tongue, Katsuki knew his Alpha was close. He doubled his efforts, sucking hard and rolling Izuku’s balls in his palm.
With a roar of completion, Izuku found his release, thick ropes of cum flooding Katsuki’s mouth and throat. Katsuki swallowed greedily, moaning at the taste of his Alpha’s essence on his tongue.
Izuku stroked Katsuki’s hair as he pulled off, gentling him as he gasped for breath. “Fuck, baby,” he panted. “That was incredible.”
Katsuki grinned up at him, eyes bright and cheeks flushed with pride and arousal. “Ready for the main course?” he teased, voice rough from the thorough blowjob.
Izuku let out a low growl before pushing Katsuki onto his back and lifting his legs.
Katsuki gasped when Izuku’s fingers found his slick hole, already starting to flutter and ache with need.
“You’re so wet for me already,” Izuku purred, circling Katsuki’s entrance with a teasing touch. “Can’t wait to sink my cock into this tight little hole.”
“Yes,” Katsuki whimpered, hips rolling up to chase Izuku’s touch. “Need you inside me, Alpha. Want to feel you fill me up.”
“Get properly on the bed and present yourself then,” Izuku growled, a deep, possessive sound that made Katsuki shiver with want as he rushed to obey. Izuku followed him onto the bed and watched with greedy, lust-filled eyes. He slicked his fingers and pushed them inside Katsuki’s heat, careful and thorough in his preparation.
Katsuki was panting and trembling by the time Izuku deemed him ready, his entrance soft and pliant, fluttering around the press of Izuku’s thick cock head.
Katsuki couldn’t help but let out a small gasp as he felt Izuku’s thick length start to stretch him open.
“Izuku, you’re so big,” he whimpered, hands fisting in the sheets as he tried to relax into the invasion. “It’s too much.”
“Breathe for me, Kacchan,” Izuku encouraged, starting to sink into the welcoming warmth of his Omega’s body. “That’s it, nice and slow.”
Katsuki focused on his breathing, on the stretch and burn of being filled so completely. It was a lot, more than his fingers or toys had ever been, but it felt amazing. Like Izuku was made to be inside him like this.
Izuku gave Katsuki a reassuring smile before leaning down to capture his lips in a tender kiss. He continued to push forward, inch by careful inch, until finally, he was fully seated inside Katsuki's tight heat.
“Oh wow,” Izuku groaned, forehead pressed against Katsuki’s as he savored the sensation of being surrounded by his Omega’s velvety walls. “You feel amazing, baby. So perfect and snug around my cock.”
Katsuki could only moan in response, feeling deliciously full and stretched to his limit. He could feel every ridge and vein of Izuku’s shaft as it pulsed inside him, and he knew he would be feeling this for days to come.
Slowly, Izuku started to move, withdrawing until just the tip remained inside before pressing back in. He set a gentle pace, letting Katsuki adjust to the size and girth of his Alpha’s thick cock.
As the pleasure built, Katsuki found himself wrapping his legs around Izuku’s waist, heels digging into the small of his back as he urged his Alpha to take him harder, deeper.
The new angle had Izuku’s cock dragging over Katsuki’s prostate with each thrust, sending sparks of ecstasy shooting up his spine.
Katsuki clung to Izuku’s shoulders, nails digging into his skin as he was rocked by wave after wave of ecstasy. He could feel his heat building with each thrust, could feel himself getting closer and closer to that moment of completion.
“Fuck, I can feel you getting close,” Izuku growled, snapping his hips faster, harder, chasing his own end. “Come on my cock, baby. Want to feel you squeeze me. I’m gunna fill this sweet little hole with my cum. Mark you from the inside out. You’re mine, Kacchan. My Omega.”
“Yes,” Katsuki cried out, back arching as his orgasm crashed over him like a tidal wave. “Please, Alpha! Claim me, make me yours!”
Izuku didn’t hesitate, his teeth sinking into the junction of Katsuki’s neck and shoulder with a primal growl. The sharp pain was quickly replaced by a wave of euphoria as their bond snapped into place, a rush of emotions and sensations flooding them both.
Katsuki’s body tightened around Izuku’s cock as his orgasm hit him like a freight train, his vision whiting out as pleasure overtook him. He could feel Izuku’s knot swelling inside him, locking them together as his Alpha emptied himself deep within his body.
“Fuck, Kacchan,” Izuku groaned, his hips stuttering as he rode out his own climax. “You’re perfect… so perfect for me.”
Katsuki’s heart raced as he leaned in, teeth grazing the junction where Izuku’s neck met his shoulder. He could feel the alpha’s pulse beneath his lips, quick and steady, a rhythm that matched the pounding of his own heart.
Izuku’s hands gripped Katsuki’s hips, fingers digging into the flesh there as if to anchor himself. “Do it,” he urged, his voice a low growl that sent shivers down Katsuki’s spine. “Mark me. Make it official.”
Katsuki didn’t need to be told twice. With a feral snarl, he sank his teeth into Izuku’s neck, biting down hard enough to draw blood but not enough to cause true harm. The taste of copper flooded his mouth, metallic and heady, and something inside him sang with satisfaction. Izuku let out a guttural moan, his hips jerking reflexively as the bite sent waves of pleasure crashing through them both.
Katsuki could feel it, the bond snapping into place, an unbreakable tether that tied them together on a level deeper than flesh and bone. It was electric, overwhelming, like every nerve in his body had been set alight. He released Izuku’s neck with a satisfied lick, his tongue swiping over the fresh mark to clean away the blood.
"Mine," Izuku breathed, resting his forehead against Katsuki's.
"Yours," Katsuki agreed. “As you are mine."
“Always.”
The connection that snapped into place between them was everything Katsuki had dreamed and more. He could feel Izuku's emotions, his love and satisfaction and overwhelming contentment. Could sense his Alpha's fierce protectiveness and pride and dedication.
"Perfect," Izuku murmured, rolling them over so Katsuki could rest while Izuku’s knot still connected them. "You're perfect."
Katsuki hummed his agreement, already planning their future. They would continue being heroes, continue being partners in every sense of the word. And someday, maybe, they would have pups.
But that was for later. For now, he had his mate, his Alpha, his Izuku. The boy who'd been torn away from him at seven had found his way back as a man, and they were never going to be separated again.
"I love you," he whispered against Izuku's chest.
"I love you too, Kacchan. Always have, always will."
As they settled deeper into the nest, Katsuki felt the last piece of his soul slot into place. He was home, finally and completely home, in the arms of the person he'd been meant for since childhood.
Outside, the world continued spinning, villains plotted and heroes prepared to stop them, life went on in all its chaotic complexity. But inside their nest, wrapped in Izuku's arms and surrounded by the scent of their bonding, Katsuki had never been more at peace.
They were fate mates, reunited at last, and nothing would ever separate them again.
***
- Three Years Later -
"Kacchan, have you seen my—oh." Izuku stopped in the doorway of their shared home office, eyes widening at the sight that greeted him.
Katsuki sat in his desk chair, one hand on his laptop keyboard, the other resting on the gentle swell of his belly. At six months pregnant, he was just starting to show properly, though he'd been complaining about his changing center of gravity for weeks.
"Don't even start," Katsuki said without looking up from his screen. "I'm perfectly capable of working from home while pregnant."
"I wasn't going to say anything," Izuku said, coming up behind him to press a soft kiss to the top of his head. "Just that you look beautiful."
Katsuki leaned back into the touch, letting Izuku's hands settle over his own on his belly. "Our pup's been active today. I think they're going to be a hero like their parents."
"With your stubbornness and my strategic mind? Definitely a force to be reckoned with," Izuku agreed. "Have you thought any more about names?"
"I like the ones we discussed," Katsuki said. "Traditional names with strong meanings."
They'd been debating names for months, wanting something that would honor both their families while giving their child their own identity. It was one of many conversations they'd had about the future, about balancing their hero careers with parenthood, about the kind of parents they wanted to be.
"Whatever we choose, they're going to be loved," Izuku said softly. "So incredibly loved."
Katsuki smiled, covering Izuku's hands with his own. "Yeah, they are."
Outside their window, the city buzzed with afternoon activity. Heroes patrolled the streets, protecting people who went about their daily lives mostly unaware of the constant vigilance keeping them safe. It was the world they'd helped build, the peace they'd fought for.
And now they were creating new life to inherit that world, a child who would grow up knowing they were wanted and cherished, who would understand that love came in many forms and that family was about choice as much as biology.
"I love you," Izuku murmured against his hair.
"I love you too," Katsuki replied, feeling their bond pulse with warmth and contentment.