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A large box, carefully wrapped in orange and green gift paper lay alone on his nightstand. A meticulously crafted bow sat on its top, with a small handwritten note tucked away in one of the decorative folds of the paper.
Izuku had insisted that no one get him a gift. How could he ever accept anything from the people who spent years contributing to the revival of his childhood dream? Of course, none of them listened and still threw him a surprise party.
They had thoughtfully organized an inarguably perfect surprise party for his 26th birthday. Uraraka reserved an entire restaurant to allow all of his friends to let loose in privacy. Jiro set up a makeshift stage for anyone to give a karaoke performance. Sato supplied an award-winning dessert spread, Kirishima and Mina set up a seemingly endless lemon sour tap.
It had been… a lot.
And at the end of the night, when one of the hired drivers dropped him off at his apartment, the tight smile on his face faded and he was left alone, still staring longingly at the damn box perched on his nightstand.
Kirishima had handed the gift to him as they all left, a little too drunk to give him any real explanation except the gift was from Kacchan.
His claws itched on the tips of his fingers, begging to be released, his inner alpha enraged in the change of plans. Because if he was being honest, he was always grateful for his friends, but all he had wanted for his 26th birthday was to spend the day with Kacchan.
Kacchan promised they would spend the weekend together at UA training grounds, working on Izuku's mastery of his new suit. Kacchan even planned on prepping all their meals so they didn't have to stop training to cook. It was going to be an entire weekend of wrestling, eating Kacchan's cooking, and then spending their evening watching their own fights to give each other pointers.
A whole weekend of Kacchan's devoted attention, it was a dream come true. Izuku had been counting down the days until his birthday for over three months, his eagerness growing with each day coming to an end.
Until yesterday, when Kacchan called out of the blue, canceling their well-formed plans after coming down with a cold.
A cold.
It was unthinkable their carefully orchestrated plans could be taken down by something so simple as the common cold. And yet here Izuku was, sitting on his bed alone staring at the gift he should be opening with Kacchan by his side, acting nonchalant as Izuku showered him with endless praise.
Izuku begged him to come over anyway. What was a suffering snotty nose to be able to share the entire weekend with Kacchan? They didn't need to train; they could spend the weekend relaxing and watching movies instead.
If the public found out, many might think it is a little strange for two alphas to spend so much time together, especially if it was in another alpha's den. But his relationship with Kacchan had always been a little strange. Why worry about it now?
“Idiot,” Kacchan had scoffed, his voice dangerously attractive. “Do you want to get your entire class sick? You have brats to think about, you can't keep running into things without thinking.”
Despite his completely reasonable logic, Izuku could not help but jump to another conclusion. Maybe Kacchan didn’t want to spend the weekend in Izuku’s den because he found someone else to spend the weekend with.
No one had been surprised at Kacchan's presentation; he was the prime example of an alpha after all. Presenting their second year of middle school, he basically ran the entire building, even teachers bared their necks under his commanding scent.
His intoxicating scent.
Izuku’s fingers lingered over the folds of paper, tracing every crease like it held some secret. His claws lengthened almost involuntarily as he pressed gently against the surface, dark thoughts of what could be inside polluting his mind.
He needed to wait to open it with Kacchan when he felt better. Knowing that would be the only time his friend would accept praise without a fight. His proud chin raised, his cheeks flushed as Izuku gushed over his amazing gift.
Carefully, Izuku dipped his finger under the folded edge. The tight paper squeezed against his thick, scarred fingers, coaxing his claws all the way out. His hands trembled as he lifted the package up to his nose, wanting to drown in the rich scent Kacchan accidentally coated the paper in.
Venomous fangs lengthened from his gums, the deadly pair poking his bottom lip, dripping out venom as Kacchan's scent overtook his nose. Just as his claw met resistance, denying him further entry–
“A PHONE CALL IS HERE; A PHONE CALL IS HERE-”
The gift in his lap tumbled to the floor, the haze in his eyes vanishing as a wave of awareness set his cheeks on fire.
What was that?
His vision was a little blurry, his face covered in a light sheen of sweat, he slid his finger across the glass screen without looking without thinking.
“Izuku speaking,” His words held a slight lisp, his fangs refusing to shorten.
“Oi dumbass why are you talking with your fangs out like you just presented?” A breathy voice growled over the speaker.
“Kacchan,” Izuku said, his voice thick with devotion, his earlier embarrassment overshadowed, “You called.”
“Way to bring up the obvious.” He scoffed, “What has you so busy you haven't bothered calling me? I know Eijiro gave you the gift, you not like it or something?”
“What!?” Izuku scrambled off the bed, landing with a loud thud on his hands and knees next to the pristine gift. “No, I-I just haven't opened it yet.”
“What are you waiting for? Stop being weird and open it.” His words were harsh but there was a slight tremble in his voice.
A smile grew on Izuku’s face, “I’m sure I will love whatever Kacchan gives me.” He brought his legs in, sitting cross-legged with the large gift in his lap.
His callused fingers stroked the edges of the paper, his breath hitching when his claws found a thin piece of tape holding the paper together.
“Quit panting like a dog and open the gift dammit.” Kacchan's breathing was a little heavy over the speaker so he had no room to talk, but Izuku had to tread carefully. Kacchan was easy to spook, if he even though Izuku could tell he was nervous or flustered, he would hang up right away.
Izuku held his breath, gaining control of his thundering heart. His claws made easy work of the double-sided tape, slicing through the thin plastic like it was not even there. The sheets of paper fell neatly to the sides of the sturdy paperboard box.
His hands trembled as he grasped the top of the box, unable to bring himself to reveal its contents. "Can't I wait to open it with you?”
For a few seconds, all Izuku could hear on the other end of the phone was Kacchan’s irregular breathing. “No nerd,” he finally panted, “I want you to open it now, I need to hear your reaction.”
Izuku never could deny Kacchan anything. His hands moved before he could think, taking off the top in one smooth motion revealing the most beautiful sight he had ever seen.
A blanket.
Izuku’s fingers sank into the large, hand-woven red, yellow and blue blanket and brought it to his nose. The deep masculine scent utterly saturated the thick wool strands. The scent was so strong it was as if Kacchan had rubbed every centimeter of the wool against his glands before weaving it together.
A deep rumble vibrates in his chest, his fingers mindlessly digging deeper into the ultra-soft yarn, wishing to bury himself in the gift. A few months ago Izuku accidentally revealed to Kacchan during one of the meetups his wish to have a blanket for his den. He never thought the other alpha would make this dream come true as well.
“What-what do you think?” Kacchan asked, his voice tight.
What did he think? Izuku could not even try to form words, his mouth too full of venom as he rubbed his face into the material.
“I love it,” He mumbled into the blanket, unwilling to tear his nose away even for a second.
“Tell me what you like about it?” Kacchan asked, his voice soft, a hint of desperation at the end giving away the true nature of his question. Tell me what you like about me.
Izuku’s face sank further into the blanket, his eyes glazed over from taking in so much of his intoxicating scent at once. If he wasn't on the strongest suppressants legally sold he was sure he would flip into rut.
“Kacchan made the ideal blanket.” He rubbed his cheek against the material, careful to keep it away from the glands on his neck; he didn't want to risk his scent overtaking it. With his face so close it was impossible to inspect every stitch like he wanted but he could easily make out the inspiration for the design of the blanket.
“Its soft, so soft around my fingers.” He pressed each digit deeper, mesmerized at how tight the strands were woven. “The knit is really uniform and you managed to keep the colors from blending at the ends so the silver age pattern actually forms a perfect circle in the center of the design. That must have taken forever, switching the yarn back and forth just to keep everything so clean. I mean, the way the colors line up exactly without any bleeding… you’re-it's amazing.”
“It took four months.” Kacchan grumbled, his voice heavy and deep, reminding Izuku of his cold.
For four months, Izuku had Kacchan’s undivided attention. While he moved through his daily routines, Kacchan had quietly dedicated his evenings weaving together the strands of wool. An intimate act of dedication usually performed by courting omegas, and Kacchan did it for him.
The last ounce of self-control Izuku had been clinging to crumbled, his underwear tightening, his head dizzy as his blood rushed to fill his cock.
“Kacchan,” Mindlessly, Izuku’s large hands snake into his boxers, palming over his erection. He held the phone away from his face and let a small groan escape his lips, his control slipping fast.
“Don’t tell me that’s all you noticed.” Kacchan growled, his words blurring together, his tone a little higher in pitch.
Izuku tilted his head, like a dog with a bone. He wrapped his fingers around his length, wincing at the dry rub into his fist. He couldn’t stop, even to grab so lube from his nightstand, too desperate to hold onto this moment.
“It smells just like you. Your quirk makes your scent extra strong due to the excess amount of sweat your quirk produces.” His hips lift off the floor, fucking into a fist he knows does not even compare to how Kacchan would feel around him.
“So you like how I smell?”
Izuku’s breath hitched, imagining the cocky smirk decorating Kacchan’s face, the way the sides of his eyes crinkle and head tilted ever so slightly… he had to bite his lip, a pathetic whimper almost escaping his mouth.
The more of it he took in, the hazier his brain became. It was like his first rut all over again. Desperate and hidden away in the dorms from everyone, clutching one of Kacchan’s sweaty tank tops he had stolen from his laundry after their shared training.
“Yeah?” Kacchan’s words were tight, his voice hoarse. “What do I smell like?”
“Kacchan,” he couldn’t keep the whine out of his voice this time. It was a completely inappropriate question to ask, even among close friends. Of course Kacchan never seemed to care about unspoken rules. His fingers curled possessively into the blanket as he leaned in, breathing deeply like he needed the scent to ground him. It encompassed his lungs, settling deep in his chest like it rightfully belonged there.
He struggled to hold the phone tight against his ear, wishing selfishly he had the strands of Blackwhip once again to allow him to hear Kacchan's voice easily as he stroked his cock.
“You’ve always smelled warm and a little sharp? Like a sugary pastry left in an oven just a bit too long. Not burned, exactly, just kind of caramelized.” Izuku wants to stop his mouth from moving, he should not be saying any of this, he was already so out of line. But he couldn't, if anything his rambling grew even more frazzled as the hand in his pants increased in speed, his lower abdomen growing tight.
“And when you use your quirk, a smoky note comes in and it blends it all together to create a scent that is…” He held his breath, a wave of pleasure tittered on the brink, ready for the smallest spark to set him off. “A scent that is made for me.”
“Izuku,” Kacchan whimpered. A long, broken sound carried over the phone and shook Izuku out of the lustful pit he had fallen into.
Kacchan never whimpers. Ever. Unless… unless he is hurt.
The warm tightness in his abdomen immediately dissipated, replaced with a sickening twist. Kacchan lied to him. He was not sick with some common cold, whatever he has come down with must be serious.
Izuku cursed himself, shoving his erection back into his suit pants, wincing as the overly sensitive skin dragged across the cotton of his underwear. He should have known better that Kacchan would lie about something like this, not wanting to ruin Izuku’s birthday over something he considered trivial.
“Izuku,” a desperate growl from the other end of the other end of the line as Izuku bolted out of his bedroom, yanking his heavy briefcase off the living room table. “Stop ignoring me you bastard, I know what you are thinking.”
He slammed his front door closed, bolting to the stairs and out of the building, ignoring the screaming coming from his phone.
“What are you doing? Don’t even think about coming over. I just- I stubbed my toe on the table ok. I am fine. Don’t come over, I-I don’t want you here.”
If Izuku had not been messing with the controls on his briefcase to release the mechanics of his suit he would roll his eyes. It had been years since Kacchan used his words to create a distance between the two of them. Kacchan was out of practice if he thought that half assed insult would keep Izuku away.
“Izu-Deku I mean it!” Kacchan's voice grew in panic as the soft whirling sound of his suit sounded, his feet lifting off the ground. “Would you listen to me for once!”
His body rocketed into the sky, the flight route to Kacchan's apartment already preprogrammed.
“You shitty obsessive freak,” Kacchan hissed, his suit now taking over from his phone, “Why can’t you ever mind your own business!”
The motors in his feet shifted gears, the neon lights of Tokyo blurring together in the night sky. In normal circumstances he could reach Kacchan's apartment in less than ten minutes. With his suit in third gear he could already make out the skyscrapers outline.
A few more seconds in the air and he could make out the large balcony attached to Kacchan's apartment.
Reluctantly, he slowed his speed, not wanting to crash through the reinforced glass doors… again. His heavy metal boots clanked onto the stained concrete launchpad Kacchan had specially installed after his suit was finished.
The thick blackout curtains blocked him from seeing inside the apartment, and only a small sliver of blue light even hinted at the presence of life. There was no lock on the door, why bother? Anyone brave enough to break into a pro’s home would never be stopped by a thin piece of metal. He pushed the thick, heavy curtain to the side, the only light in the living room, a blue screen on the large TV.
“Kacchan!” he yelled, making a straight shot to his bedroom. The entire apartment felt warmer than usual. Kacchan must have left a window open.
“Go home now, nerd!” He yelled from behind the solid door to his bedroom, to his den.
“No,” Izuku reached for the door handle. “You should have told me how sick you were! You need to go to the hospital, especially with your heart.”
His fingers push down, turning the knob.
“Deku!” He snarled, his voice a little louder as Izuku cracked the door open. “Please.”
He pushed the door further open anyway, his nose catching onto the situation seconds before his eyes could process the sight in front of him.
Oh
Oooh
Now it all makes sense.
Kacchan was kneeling on the floor of his den, his body hunched over a reinforced rut breeding bench. His cheeks were flushed, his hands flailing wildly in the air as he tried in vain to both hide his naked form and shoo Izuku out of the room.
But Izuku could hear nothing, his ears ringing as the smell of sex and rut pushed all rational thoughts out of his mind.
Instinct was a tricky thing. What was once considered necessary for survival is now seen by most as another annoying trait that evolution has yet to eliminate. Izuku was somewhere in the middle of the argument, too focused on the evolution of quirks to ever really care about the outdated traits his secondary gender would give.
That is, until every cell in his body was powering up, adrenaline pumping through his blood faster than he could process. His fangs, already distended from earlier, dripped with fresh venom. His claws dug into the meaty palm of his encased metal hand.
Kacchan continued to flail on the ground, his palms facing outwards, sparking dangerously. Still Izuku took a step forward, his hands curled outwards.
There was no stronger pull of instinct an alpha could face than encountering another alpha mid rut. The guttural urge to fight was said to overpower all reason, to control an alpha's frontal lobe until the threat was eliminated. It was an instinct Izuku was not unfamiliar with, alphas often committed crimes while deep into their rut, their self-control at an all-time low.
Izuku never had a problem with his control before, always able to keep a tight lock on his self-control and subdue each threat accordingly. But this threat was wiggling around pathetically. This threat whose knot was currently buried in a rut toy had his instinct urging him to take a step forward.
“Why can’t you ever listen?” the alpha on the ground said, their voice cracking as their hands ignited on the strong metal breeding bench where his chest rested.
His metal-encased feet took another step, the particle strands of Blackwhip creeping out of suit, slithering their way to the threat in front of him. His vision narrowed, locking in on the dangerous warning sparks sent his way. The heat blasts landed harmlessly on his suit, but the warning was clear. This alpha wanted him gone so he could keep whatever omega he had locked in his den for himself.
Izuku’s inner alpha reared to life, snatching away any rational thought. He needed to eliminate this threat, his instincts demanded this.
The snaking strands descend on his target in seconds, taking control of each of their limbs, restraining them even tighter against the metal bench.
“Izuku!” His opponent snarled, their body fighting the confinement. “Izuku! What the fuck are you doing?”
The strands pull taut, keeping the threat contained as he takes the final steps needed to stand over the helpless alpha.
There was little light in the warm, stuffy den. The cracked bathroom door adjoining the room provided a small sliver of warm yellow light, striking down the middle of the bound alpha. It caught in the wispy blond hair, giving it a soft golden appearance. The sight sparked a glimmer of recognition in his mind, easily extinguished with another wave of adrenaline as the alpha started to struggle against the bindings.
“You pathetic bastard, get control of yourself!” Small explosions set off across the slick body, but they had no impact on the dark strands covering even more of his exposed skin.
Izuku's fangs begged to sink into the back of the alpha's muscular neck. To utterly conquer the being underneath him into submission, pumping Kacchan's glands so full of Izuku’s scent, his dominance would be unmistakable. Only then would the threat be contained, and his inner alpha would be satisfied.
He fell to his knees, his chest rumbling with pleasure as his head descended to the exposed neck in front of him, his fangs dripping with venom.
“You idiot, snap out of it before you do something you regret!”
Of course the alpha beneath him would be angry; it was only natural to resist a display of dominance. Izuku was unsure why the alpha beneath him thought he would regret this. This was exactly what his instincts demanded. He loosened his jaw, the tips of his fangs scraping against the slightly raised skin.
“Deku, don’t you dare say I didn't warn you!”
The oily skin rich in pheromones hit his tongue as his mouth closed around the alphas neck and for a flash Izuku could think clearly, but to his own horror, the second of clarity was not nearly enough time to stop his jaw from clenching down, filling his mouth with the blood and scent of his best friend as his fangs buried themselves in his glands.
The glands of his alpha best friend.
The immense pleasure of his venom sacs emptying was nearly blinding, the pleasure nearly inescapable. Only years of practice controlling his heart allowed him to lurch backwards, his fangs unceremoniously leaving the skin. His teeth throbbed in outrage, unable to complete their job.
‘K-Kacchan?” His entire body trembled; the urge to swallow the blood, to revel in his partial claim, was strong, but his shame overpowered his instincts.
He covered his bloody face, giving them both some much-needed privacy. “Kacchan,” He sobbed the name like a prayer, bowing his head until his hands connected with the wooden floor.
“I am so sorry! I never thought you would be in a rut! I thought you were just being stubborn as always, so I did not prepare with scent blockers. Still I should have never barged into your den like that, I forgot myself. I have never reacted like that before to another alpha, I promise I normally have more self-control–” He rambled on, stumbling over his words. Incapable of even processing the severity of his mistake.
And worse, he was incapable of processing just how much he enjoyed making that mistake. His inner alpha preening at the sweet metallic taste coating his tongue.
“Zuku,” A muffled voice sounded in front of him, “Amn it, Zuku, stop sulking and fucking help me.”
Reluctantly, his head left the cool wood floor, ready to face the scolding of a lifetime.
Instead, he was confronted by what was perhaps the greatest trial he had ever encountered. Kacchan was still bound tightly with Blackwhip, the ribbons of electrodes and particles wrapping his skin like the perfect birthday present. Even better than the one he already unwrapped.
“Get this shit off of me now!” Kacchan snarled against the strand of Blackwhip gagging his mouth. His muscles bulged against his bindings, but his resistance only made the ribbons tighten.
“Uhh- right, of course.” Izuku’s clawed fingers pressed frantically at his suit's control panel, unable to calm his mind enough to order the strands back normally.
“What are you doing!” Kacchan screeched, the strands rapidly expanding across his skin, now covering his chest in hundreds of tiny branches. Branches that somehow managed to circle and pinch the pink tips of his exposed nipples.
“I-I don’t know! I can’t control it. Blackwhip isn't responding to the control panel.”
As if on cue, the strands on Kacchan’s generous chest contract, grouping the pecs as if they were breasts. An outraged moan left Kacchan’s flushed lips, a small strand of spit dripping down his chin.
Forgetting the control panel, Izuku closed his fingers around the thick strand invading Kacchan's mouth, tugging on the stubborn appendage like it was a rooted plant.
It didn't even budge.
If the moment was not so hectic, Izuku would have whipped out his notebook to record the tremendous amount of force the strands could resist. Kacchan's replication of Blackwhip was truly incredible. The suit's gears loudly turned as he applied more and more force to his pull, his biceps straining, but the strand would not leave Kacchan's warm, wet mouth.
Small tears of frustration built in the corners of his eyes. “Damn it,” he cursed, spreading his knees open to steady his stance. Kacchan needed him to do this; he needed him to fix this problem, and he couldn't even do that. What kind of alpha was he?
Head hung low in shame; unable to bring himself to meet Kacchan’s glaring red eyes he ripped his useless hands away. Staring down at the offensive appendages, he clenched his fists. Why? Why wasn't he strong enough to free Kacchan from his own suit?
Frustration boiling, Izuku grabbed the bottom of his wrist, pressing and releasing the glove, freeing his useless hand to the air. The scarred hand started back at him mockingly, reminding him of all the power it once held.
“Izuku,’ the naked body in front of him shifted, “Zuku, come on, are you really going to pout when I am the one tied up here?”
Eyes full of wobbly tears, Izuku lifted his eyes to face his shame.
“Stop being a crybaby and try again,” Kacchan rested his flushed cheek against the cushion on the metal breeding bench
Izuku wiped a couple of the sticky, fallen tears on his cheeks away, nodding like an idiot. His hands trembled as he closed in on Kacchan's mouth, how Kacchan's little fangs had sunk into Blackwhip. With his hands free of his metal gloves, he was able to carefully work two fingers into Kacchan's mouth, gripping the gag to attempt to remove it from his mouth.
Except when he gave a small tug, his fingers sank into the electrode particles.
“Huh!?” The tips of Izuku’s clawed fingers changed in shape, the once stiff strand molding around his hand before sinking into his skin, disappearing into his body.
For a second, he was frozen, too mesmerized by how Blackwhip left to realize he had two fingers resting on Kacchan’s textured tongue. He unconsciously spread out the digits, enjoying the tightness, the way his molars sandwiched in his thick fingers, while his tongue stroked the tender skin on the sides of his fingers.
Observing the rest of the stubborn web of Blackwhip coating Kacchan, Izuku realized how he could free his friend and redeem an ounce of dignity.
“I have to use my bare skin to free Kacchan.” He mumbled, allowing his fingers to linger in the warm, wet heat a second longer than needed.
Kacchan’s knowing red eyes met his, narrowing as he stretched his stiff jaw. “If you know how to fix this shit, then what are you waiting for?”
His strong fingers crept their way down Kacchan's sweat-slick skin, following the possessive lines of Blackwhip down his neck and shoulders slowly, allowing the strand to absorb back into his skin.
He ignored the instinctual pull to stroke the pad of his thumb over the blunt puncture wounds he'd left on Kacchan’s scent glands. He already caused enough trouble tonight; the last thing he needed was to accidentally milk Kacchan's scent glands, filling the room with even more of his intoxicating scent.
So he moved his hands lower, brushing past the edges of Kacchan’s collarbones, and settling on the mounds of his chest. There had to be hundreds of strands here, each branching out from the tight ring surrounding each of Kacchan’s taunt pink nipples.
Carefully, he pressed the pad of his middle fingers directly on the center of the textured skin, incapable of looking away as Kacchan's hips ever so slightly fought against their bindings, rocking into the breeding bench that was still milking his knot.
Izuku’s thumbs joined the effort, pinching the bud and tugging down, absorbing the particles as a soft, almost unregistrable sound escaped Kacchan’s flushed lips.
Izuku’s head whipped up, holding his breath as he tugged on the tips of his chest again, producing the same small whimper. A sound not dissimilar to the one he had heard over the phone back what felt already like a lifetime ago.
“Kacchan,” His fingers spread out across the muscles, massaging the generous tissue, “Were you fucking into this bench while we were on the phone?” He uses his index and middle finger to roll the taunt nipples, any trace of Blackwhip already gone. “That’s ok, because if I am being honest, I was stroking myself almost the entire time we were on the phone.”
He shifted one hand lower, following his replicated quirk down the muscular lines of Kacchan’s back. Mesmerized by how each muscle trembled underneath his fingers. The strongest man he knew was reduced to a quivering mess. It was the most arousing sight Izuku had ever encountered. Unable to contain his own excitement, the erection he had forgotten about in his rush and later shame resurrected.
The haze of instinct overtook his eyes once more, pushing his hands further down Kacchan’s toned back until his hands settled on the generous globes of Kacchan’s ass.
“Hey! Pervert, knock it off and finish the job. You still haven't removed your damn quirk from my chest.” The alpha underneath him snarled, thrashing against his bindings once more.
The tips of Izuku's claws tore away a small layer of skin as he gripped each cheek, ignoring the half-hearted protest as he spread Kacchan open to his view. And there, hidden away, was a flash of metal.
“Fuck off!” Kacchan bucked his hips, his leg rearing up to almost make contact with Izuku's cheek. Instead, the heel of his foot landed into Izuku’s palm, “You will regret this tomorrow, so just fuck off!”
Regret?
How could he ever think Izuku would regret this?
Izuku cocked his head to the side, studying the man beneath him. His beautiful face was scrunched, his eyes settled squarely on the floor, his weight was constantly shifting, his hips pulling back against the stubborn knot locking him in place.
“Please Kacchan,” Izuku begged, his instincts begging him to complete what he had started.
Glowing red eyes met his, narrowing the longer they stared at his tearstained face. “God damn it,” he sighed, his lower body relaxing, knees spread wide, giving Izuku the perfect view of the metal piece that had caught his attention earlier. “Don’t come crying to me about this later.”
Izuku’s greedy hands immediately return to Kacchan’s waiting ass, further spreading him apart to admire the hidden toy. He tapped his claws against the metal plug, hating how his heart contracted with jealousy. Without any warning he used the knuckles of his fingers to grip the flared base and gave it a tug.
Kacchan's hole did not give up the plug immediately, the ring of muscle still tight, following the plug as he gently but unrelentingly pulled it free. The metal clanked against the floor as it fell from his slick fingers. Kacchan's tight pink hole for a breathtaking second stayed open before clenching shut.
Unable to help himself, Izuku pressed one of his knuckles against the warm heat, marveling how soft Kacchan was here. He used his other knuckle to spread the hole even further apart, giving him just enough space to take a long, wet lick.
Kacchan stilled, his hole tensing against Izuku’s unrelenting tongue. Izuku took advantage of his lack of motion, his tongue slimming into a fine point, twisting the to work the appendage deeper. Small bursts of precum leak from the slit on Iuzku’s untouched cock. Kacchan stopped breathing, his back muscles quivering as the tip of Izuku's tongue managed to catch him at just the right moment, stubbornly advancing until the tense rim squeezed his tongue so tight.
Small explosions go off at the sides of his head, pushing him back before he can further explore. “I’m not some fucking omega Deku! Either fuck me or get the hell out of here and let me take care of myself!”
“But Ka–”
“Deku, I am a minute away from walking out my front door naked and fucking the first omega I can find if you don’t get a move on!”
The instinctual haze he had been fighting to keep contained sparked back to life in an instant. He clawed at his suit, freeing his heavy cock and lining it up against Kacchan’s hole.
He held the head of his cock, pressing downwards with enough force, he was finally able to push the tip inside. Already stars began to fill his vision, it took everything inside him not to slam his hips forward, burying his length inside. Somehow, he held himself back, remembering Kacchan was not built to take cock like an omega; he would have to be opened slowly, and even then, he may not be able to handle Izuku’s knot.
His body trembled as he sank his claws into either side of Kacchan’s hips. Holding them both steady as he sank another centimeter inside the impossible heat. He was too far gone to even form words, his fans fully distended until they nicked his bottom lip, venom dripping down his lips.
Another glorious centimeter and he was ready to retire, to spend every day locked inside Kacchan, holding him close in their shared den, scenting him, rutting into him until their scents were indistinguishable.
He pulled back, watching as Kacchan’s hole followed his cock, tight around him until only the head remained. Kacchan made soft mewls in the back of his throat, his back tense, arching off the metal breeding bench. Izuku pushed his hips forward, mesmerized watching his cock sink further inside, and Kacchan was taking almost half of his cock. Kacchan took him so well, only a few tears were staining his cheeks as he sunk further inside this time, not stopping until his hips were flush against the skin of Kacchan’s perky ass.
His chest rumbled and he leaned over Kacchan’s overheated back, admiring the few remaining strands of Blackwhip still tormenting the alpha. He wanted to give Kacchan time to adjust to his invasion, but with each breath the heavy ache in his cock grew more unbearable.
His hips drew back, the room air cooling his wet cock, reminding him why he wanted to stay buried inside. He snapped them forward, the stroking pleasure enough to nearly have him pop his knot.
“You knot head,” Kacchan said through clenched teeth. “How big is your stupid fucking cock.”
Izuku internally preened, snapping his hips even further forward until Kacchan's bickering slowly morphed into broken moans. He wanted this to last forever, but already he could feel the tight pleasure building in his lower stomach, winding itself tight.
He collapsed onto Kacchan's back, caging him in with his arms, his neck easily accessible, the mark he left earlier still wet with drips of venom. With the pleasure tightening, he sank his fangs deep into the glands, not stopping until his mouth was flooded with Kacchan's scent.
Now anyone who even catches a sniff of Kacchan will know who he belongs to. With the mental satisfaction of their scent bond complete, the heavy throbbing ache in his cock spiraled out of control, he could no longer control his thrusts.
The alpha beneath him was no better; pathetic whimpers tore from his throat, his entire body trembling underneath Izuku. His hips sputtered out of rhythm, towards Izuku thrusts, away from them; it was impossible to tell. All he knew was the pleasure he had been chasing all night was finally here.
Blinding flashes of color filled the darkness as he struggled to keep his eyes open, wanting desperately to watch as Kacchan fell apart on his cock. But the pleasure was too strong, Kacchan’s tight hole was milking him so perfectly he stood no chance. He could only hold onto the man who had always been in his life. Hold onto him as his entire world fell apart and came back together.
The pleasure only increased as he came back into his mind, the pressure at the base of his cock snapping him back to reality.
Shit! He pulled his hips back, mind still foggy with bliss.
Two pale hands shot out and claws dug into the sides of his hips. “Don’t!” Kacchan snarled. “Fuck. Don’t move.” His voice cracked at the end, his entire body limp underneath him, neck relaxed and lolled to the side, a subtle act of submission.
Izuku had to bite his tongue to stop a soft coo from leaving his lips. His bloodied claws trace up Kacchan's spine, coming to rest over the mark on his neck, heat radiating from the rapidly healing wound.
“How does it look?” Kacchan mumbled, his voice hoarse.
Izuku traced the puncture wounds. “It stopped bleeding,” he winced, “but it will leave a good-sized scar.”
“No shit,” Kacchan shifted his hips, his cock finally slipping out of the breeding bench, allowing both of them to fall to their sides, Izuku resting tightly against the other alpha's back like a jet pack. “What’s the point of marking someone if it doesn’t stick?”
“You’re not mad?” Izuku whispered into the side of his throat, wrapping his arms tightly around Kacchan's abdomen.
The alpha blew out a huff of air, a few strands of blonde hair flying off his forehead. “That would make me a hypocrite considering the second your knot gets the hell out of me I’m biting the fuck out of your neck.”
“Yeah?!” Another small jet of cum left his cock, his knot seemingly in agreement with Kacchan’s plan.
“You think I’m gonna be the only one walking around with some cheesy ass mark? Hell yes I’m going to mark you after this. You bastard, why couldn't you have been a little more patient.”
“Patient?”
“Yes, you knot head, patient! I had a whole plan for your birthday, but you had to go all feral and fuck me tonight huh.”
Izuku’s eyebrows furrowed. “Plan?”
The tips of Kacchan’s ear flushed red, his head turning to hide in his elbow.
“Noo tell me!” Izuku whined, trying to pry Kacchan’s face out of hiding.
“Fuck off,” hands swat him away like an annoying fly, “It doesn't matter now.”
“It matters to meee!” Izuku pressed a soft kiss to the blazing red cheek, holding Kacchan even tighter against his chest. “Please tell me?”
For a few seconds, there was silence, then Kacchan’s hips shifted against his, slipping his knot just a little bit deeper.
“Your rut wasn't supposed to be triggered until tomorrow.” He finally mumbled, still not meeting Izuku’s eyes.
The gears in Izuku’s head stalled, the wrench Kacchan had thrown, preventing any rational thought from forming.
“I-fuck,” Kacchan’s red eyes narrowed, finally meeting Izuku’s stunned gaze. “I scented your blanket while I was in rut to trigger yours. It should have taken all night for it to work though. I would have been ready for you tomorrow, you impatient bastard.”
“Wait. So tonight, you were-“ Izuku’s voice trailed off as his eyes caught the large metal plug resting to their right. “Wait, you planned on us having sex?”
“Yup, I would have come over to your place early in the morning and probably sat on your face to wake you up, the rut would have taken over by then.”
The glorious image made Izuku’s mouth water, “Wait, no!” Izuku whined; the weight of what he lost was tremendous. “Kacchan, can you still do that, please!”
“Hell no, you already opened your birthday present.”
“That’s not fair!” Izuku wailed, willing his past self to have a tad bit more self-control.
“Quit pouting, crybaby.” Kacchan’s hips slowly started to rock back, his tight warmth teasing Izuku’s knot. “If you want me to sit on your face so fucking bad, why don’t you convince me?”
By the end of Izuku’s birthday, he was left with a face bearing the full weight of his new alpha mate and the most perfect mark on the back of his neck.