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“You set me up!” Endeavor snarls, clearing all the items off the dresser with a destructive clang.
Katsuki tries to stand up, but Shouto puts a hand on his shoulder. “Sit,” he says. “I still need to give you stitches.” There’s a big gash through Katsuki’s eyebrow that’s probably going to scar, even with stitches, but at least it has mostly stopped bleeding.
Endeavor puts his hand on Shouto’s shoulder, and Shouto shields it with a layer of very, very cold ice that has Endeavor yanking it away. “You planned this!”
“Sure,” Katsuki says sarcastically. “He put the idea of a tournament for his hand into your head. He wanted to be left to the whims of whoever could win the tournament.”
Before Endeavor can reach around him to Katsuki, Shouto puts up another ice wall. “You set the terms,” he tells him shortly. “You didn’t trust me to choose my own mate. You trusted me so little to be your heir, that you’d rather leave my mate—and your heir—up to chance than let me choose.” Saying it out loud, speaking the reality of how little regard his father has for him, makes his temper rage under his skin.
As if sensing Shouto’s own rage, Katsuki puts his hand, knuckles freshly wrapped, on his hip. If he didn’t have to stand up to do it, he’d probably nuzzle at Shouto’s scent glands.
“Only a fool would trust an omega to make a clear-headed decision!” Endeavor says, his tone dripping with disdain. “And you.” He turns his attention to Katsuki. “You betrayed me, seducing my son behind my back.”
“He hasn’t touched me,” Shouto says, gritting his teeth. “Katsuki has too much integrity—”
“And too much respect for Shouto to risk ruining him or his reputation,” Katsuki interrupts. He shifts to look at Endeavor over Shouto’s shoulder. “Admit it, old man. I’m the best you could have hoped to win. You’re just mad that someone you thought was only good for guarding an omega is going to inherit your group.”
Finishing prepping the suture, Shouto puts a finger on Katsuki’s face to make him look back at him. “Sit still,” he warns, squeezing the split eyebrow together so he can begin stitching it, relieved that at least healing was considered a suitable thing for omegas to learn.
“Touya can inherit!” Endeavor announces.
If he weren’t so preoccupied, Shouto would roll his eyes. “Touya hates you so much, he would burn the whole organization to the ground,” he says flatly. “You weren’t holding a tournament of champions to inherit the group because you felt you had better options available.”
Endeavor had disowned Touya as an inferior alpha when Shouto was small—broken quirk, unworthy heir—and Touya had subsequently showed up as Dabi, setting up a rival organization. The fact he nearly killed Endeavor several months ago is why he’s felt the desperate need for a worthy heir. Even if he weren’t a beta, Natsuo’s quirk certainly would have disqualified him in Endeavor’s eyes. Fuyumi is also an omega, but, unlike Shouto, doesn’t have a quirk that makes her a valuable bargaining chip.
So Shouto was the prize.
And Katsuki had just enough rank in the group to be able to apply for the tournament. With Katsuki winning after Endeavor was so snide about him joining, Shouto would be lying if he said it didn’t make the victory a little sweeter.
“There,” Shouto says, tying off the suture. He runs a final clean cloth over them.
Katsuki gets to his feet, squeezes Shouto’s hip, then goes to stand toe-to-toe with Endeavor. “I won, fair and square. And you’d better believe I’m taking my prize tonight. I ain’t risking you going back on your word.”
For a heartbeat, Shouto thinks Endeavor is going to lash out, but his flame flickers, and he winces. Touya had dealt him quite a blow, and Shouto is pretty sure they all know that—even tired as Katsuki must be—Endeavor is not strong enough to go up against him at the moment.
There’s still a part of Shouto that feels like he must be dreaming as he watches his father back down. Katsuki just nods as if that’s the way things should be.
“We’ll be taking this room too,” Katsuki says. Before Endeavor can open his mouth to object, he adds, “You can’t possibly want him to be mated and bred in that little cell of a bedroom you allow him. I’m your heir now, and we both know I’m going to be running this show sooner than later. It’d be a show of favor in me to give me this.”
Endeavor growls, low and angry, and Shouto holds his breath.
“Six months,” he finally grinds out. “You have six months to knock him up, or I’ll find a better alpha for him.”
He doesn’t let Katsuki respond before turning on his heel and slamming out of the room.
Feeling lightheaded as he lets out his held breath, Shouto sinks down onto the seat that Katsuki had been on while he’d treated his wounds. Katsuki is by his side, kneeling before him in a heartbeat.
“You okay, princess?”
Shouto laughs, soft and almost a little hysterical. “I can’t believe that worked.”
Scratching at the back of his head, Katsuki looks a little sheepish. “I didn’t expect it to be that easy either,” he admits. “He must be worse off than we thought.”
Shouto doesn’t know; Fuyumi had been the only one allowed to treat Endeavor after the fight, and she hasn’t shared any details of his wounds with even Shouto.
“Ask me in the morning,” Shouto tells him. He reaches out and runs a hand down Katsuki’s shoulder, lightly tracing the lines of the dragon tattoo rising up Katsuki’s arm to his chest. “Are you really planning to mate me tonight?”
A slight flush colors Katsuki’s cheeks. “Unless you really don’t want me to…” he says, looking away.
Shouto doesn’t think, just moves. He takes Katsuki’s face in both hands, leans down, and kisses him, hoping he does it right. He thinks he must be, because even just the kiss—after pining for over a year—sends pleasure racing through him. His body tightens, his cock hardens, and heat builds low in his belly.
So distracted by all of the sensations he’s experiencing, he yelps when Katsuki stands and sweeps him into his arms, carrying him over to the bed and laying him down on it gently. His own shirt was already long discarded, and Shouto can’t help but frown at some of the bruises he sees.
“Hey,” Katsuki says, grabbing his hand and putting it to his chest, over his heart. “I’m here. I’m strong. You ain’t getting rid of me that easily.”
He climbs onto the bed, still holding Shouto’s hand over his heart, and Shouto sits up to press his forehead to Katsuki’s chest. “I thought I’d lose you,” he admits, finally letting himself admit it. The tournament had been a true contest, and his heart had been in his throat since Katsuki first told him he was going to enter. It’s hard to believe that it’s over and Katsuki really won, that he gets to mate the man he’s fallen in love with.
“No way would I let anyone else touch you,” Katsuki assures, his free hand passing over Shouto’s hair, stopping at the ribbon holding it back. “Can I—?”
Taking a breath to steady himself, Shouto pulls back and meets his eyes. “Whatever you want, alpha.”
A shiver goes through Katsuki at that. “Shit,” he hisses, and it takes him a moment to grip the ribbon and pull it loose, letting Shouto’s hair free. He doesn’t hesitate to dig his fingers into it, cupping the back of Shouto’s head, guiding his face up. “I’m going to take such good care of you, princess. I swear.”
“I know,” Shouto says, and he does. He trusts Katsuki with every fiber of his being. Gently, he lifts his hand from over Katsuki’s heart, then guides Katsuki’s hand to the back of his obi. “Mate me, Katsuki, alpha.”
His hand is much surer as it pulls the knot on the obi free. Once loose, the whole kimono loosens, becoming more robe than garment. They both work to get it off entirely, and once it is, Shouto is suddenly very aware of how little the kimono protects him.
Katsuki’s eyes rake over him, hungry, and his desire scents the air like a firework during a festival. Shouto isn’t sure if Katsuki’s scent has ever been quite that intense, quite that sharp. Low in his belly, something tightens again, in a way it only does when he’s on his heat.
The red of Katsuki’s irises thin to a slight ring, swallowed up by the black of his pupils before he leans in and inhales deeply over Shouto’s scent gland. “If I didn’t know better…” he murmurs against the sensitive skin.
“What?” Shouto asks, his own cock filling and uncomfortable in his underwear.
Katsuki inhales again, then says, “It smells like you’re going into heat.”
Could he be? So soon? Endeavor had insisted he go off his suppressants so that when the tournament was finished, he’d be ready to be bred by his new mate, but could the effects of the suppressants he’s taken since he was fourteen really fail so quickly?
“Do I?” he asks, and he can feel his underwear growing damp with slick.
Licking over Shouto’s scent gland sends a jolt of sharp pleasure through Shouto, and he gasps, his cock growing harder and the heat inside growing.
Teasing a fang over the gland, Katsuki says, “Yeah, you do.” He gently guides Shouto back, moving so he’s between Shouto’s legs, careful not to trap Shouto’s hair beneath him. Then he shoves the kimono back, leaving Shouto’s arms in the sleeves, and his underwear tented obscenely. Shouto can feel the blush heating his cheeks as Katsuki stares down at him. He strokes the intimate skin of Shouto’s inner thighs before moving up to grip Shouto’s underwear.
As though its existence offends him, Katsuki tears it apart, tossing the remnants aside, leaving Shouto’s most intimate places bare to him. Part of Shouto desperately wants to cover himself, but his instincts are already going to work, and he spreads his legs wider in invitation.
“You’re so fucking gorgeous,” Katsuki says, almost under his breath, as if to himself instead of to Shouto. “Gonna make you mine.”
“Yes,” Shouto agrees, his cock now fully hard and standing proud. “All yours.”
Katsuki teases his fingers through Shouto’s bush, then bends down to take the head of his length into his mouth.
Shocked, Shouto cries out, burying his hands in Katsuki’s hair, trying to pull him off. Katsuki just sucks him harder, taking more of him in, staring up at Shouto with defiant eyes carved of ruby and onyx.
“You can’t!” Shouto tries to tell him, but the protest comes out breathy and weak as the hot, slick pleasure of Katsuki’s mouth around him steals his resolve.
Still watching Shouto, Katsuki slips a finger into him. It goes in easily with the aid of Shouto’s slick, the first time in a long time Shouto’s had anything inside of him. His body grows hotter, and he whines. Without thought, he bucks his hips, trying to ride Katsuki’s finger as if that alone will make it be more.
Katsuki takes his time, adding a slow finger only when Shouto is about to come out of his own skin.
“Please, Katsuki…” he begs when Katsuki’s got three fingers in him and he’s sure that he’s going to lose his mind if his alpha doesn’t take him. His body feels hot, feels scorching, everywhere Katsuki’s touching him feels like it’s going straight to his cock, and yet, Katsuki just won’t suck hard enough. “Alpha,” he whines.
When Katsuki finally pulls off, Shouto isn’t sure if he should whimper in relief or cry in frustration.
“You sound so pretty when you beg for me,” Katsuki says, then licks a long stripe up the side of Shouto’s straining dick. “What do you want from me? Ask me for it.”
Shouto spreads his legs wide in open invitation, far too far gone to be worried about how vulnerable he is. “Knot me, Katsuki. Alpha. I need you. Need you inside…” He puts a hand low over his abdomen. Emptiness gnaws at him, like nothing he’s ever felt before, but he feels it now. Incomplete. He doesn’t know how he knows, but he knows that Katsuki can fill it with his knot.
Putting his own hand over Shouto’s, Katsuki sits up, lips swollen from going down on Shouto. “You’re in heat,” he says, inhaling deeply. “You want me so much, don’t you?”
“Yes!” Shouto keens.
“You want my knot. Want my fangs. Want my mark.”
“Yes!” The words feel like they’re sinking under his skin, teasing him, taunting him, when all he wants is to have his alpha inside of him. “Please!”
Katsuki straightens, sitting back on his knees, pulling Shouto’s legs forward, his hips up, till his cock is kissing Shouto’s entrance. “Has anyone ever touched you?”
“No,” Shouto says, shaking his head furiously. No one had ever been allowed. “Only you. Only you, Katsuki.”
He growls, leaning over Shouto, bracing himself above him with one hand next to Shouto’s head, the other firm on Shouto’s hip. “Mate me, Shouto,” he says, his voice a needy rasp. “Be mine. Only mine.”
Shouto’s hands rise to rest on Katsuki’s shoulders, and he tips his head back and to the side, baring his scent gland. “Only yours. Mate me, Katsuki.” He can see the fangs looking longer in Katsuki’s mouth than usual, and he can feel his own claws lengthen. He teases them over Katsuki’s scent glands. “And you’ll be only mine.”
“Yes…” Katsuki hisses out. “I’m gonna be yours too. Gonna spoil you, make you feel so good. My pretty princess. Gonna treat you like the princess you are.”
Every part of Shouto is screaming out to be filled, and he slides them over Katsuki’s glands, pressing harder this time, and Katsuki’s eyes flutter as if he’s been drugged. “Less talking. More mating.”
Refocusing on Shouto, Katsuki gives him a fierce grin. “As my princess desires.” He shoves forward, and Shouto’s body opens to him. Katsuki slides in, filling him, and it’s like it’s where he belongs. The sense of being filled is so right, so perfect, he comes before Katsuki’s even all the way inside. His claws dig into Katsuki’s glands, claiming his alpha, and Katsuki’s own fangs sink into his.
Feeling Katsuki’s fangs sinking into him as Katsuki’s cock does sends something inside of him spiraling. It’s perfect, meant to be. A sensation pours through him, running from his gland down to his womb, and the pleasure he feels seems like it’s building exponentially. By the time Katsuki is fully buried inside of him, he’s already coming again with a cry.
Shouto gets lost in sensation, pleasure so thick and cloying, he can’t think around it, swimming on his and Katsuki’s scents mingling, filling them both. When he feels Katsuki’s knot tugging at his entrance, he comes again, digging his claws in deeper, and Katsuki finally manages to pull his mouth free of Shouto’s scent gland, only to kiss along Shouto’s throat, urging him with touches but not words, to shift his head so he can reach Shouto’s other gland. When he does, he clamps his fangs down on it, sinking them and his venom into Shouto, even as his knot forces its way inside and swells.
Mouth falling open in a silent scream, Shouto comes again, his body going tight around his alpha, even as he feels Katsuki spilling inside of him. He can feel his body tensing and relaxing, milking Shouto’s orgasm as much as it’s milking Katsuki’s knot.
Slowly, Katsuki maneuvers them onto their sides, careful not to yank on his knot too much. Once there, he finally takes his fangs out of Shouto’s gland, and Shouto shivers, but before he can do anything, Katsuki cups his face and kisses him. His mouth is spicy with the lingering traces of his venom, but it only makes Shouto hungrier for him.
Then his whole body tenses, almost like a cramp. He breaks the kiss and cries out softly, his voice a wreck from gasping, panting, and all the noises he’s made as Katsuki takes him. As fast as it comes, it’s gone, but it still leaves Shouto feeling like he just ran a sprint.
“Shou,” Katsuki says, his own voice deliciously rough. Shouto wants to bury his face into Katsuki’s chest and feel that rumble against his skin. “Shouto!” he repeats with more urgency.
“Hmmm…?” Shouto asks, languid exhaustion overcoming him again.
Katsuki brushes his bangs back, touching Shouto’s face with such aching tenderness, Shouto can’t feel anything but treasured. “Are you okay?”
Grabbing his hand, bringing his knuckles around to kiss at them, Shouto says, “More than okay.” Sweat and spend are cooling on his skin, but Katsuki is warm, and Shouto is far too sated and satisfied to be anything other than borderline giddy.
He can feel Katsuki still watching him, but he’s happy to just snuggle and continue to let their venom and pheromones keep him floaty and content. He does open his eyes to look at Katsuki’s shoulders, curious as to the marks his claws may have left.
When he realizes what he’s seeing, Shouto sucks in a breath that makes Katsuki groan softly. Lifting a hand, he strokes the pad of a finger over the fine lines—blue over one shoulder, silver over the other—that now decorate the tops of Katsuki’s shoulders, over his scent glands.
“Katsuki…” he says, not sure what else to say, but his voice must alert Katsuki to something being off. “You… I…” He’s heard of this happening, but it’s a myth. True mates aren’t real. Mating marks don’t heal instantly for real. And yet…
Katsuk brushes a thumb pad over Shouto’s own gland, and he shivers, struggling not to moan from how good it feels. “My mark is red,” Katsuki says, barely audible.
“Yours are blue and silver,” Shouto tells him. There should be blood and cuts on their shoulders from claws and bites, but he realizes now that there’s nothing but sweat and Shouto’s seed drying on them.
Being very careful not to tug too hard, Katsuki pulls a little bit back, looking down their bodies. Shouto sees his eyes get a little wider, and the hand drops from his scent gland to trace over the skin just above his cock. It sends another pleasurable shudder through Shouto, and he moans.
Without warning, Katsuki grabs him, twisting them, until he’s on his back, Shouto sitting upright on him, still impaled on his knot, though the position drives Katsuki’s knot a little deeper and Shouto’s own cock to stir back to life.
“Shouto…” Katsuki says, and something in his voice is nearly reverent. He rubs his thumbs over Shouto’s hips, staring at his abdomen, and Shouto finally makes himself look down.
Low on his abdomen, over where his womb is, an ornate mark of twists and swirls, in the same ruby red as Katsuki’s eyes blooms. When Shouto brushes his fingers over the mark, his hand trembles.
“It… can’t be…” he says, emotions racing through him, far too many and far too fast for him to name.
Katsuki presses his own hand over Shouto’s, just as he had earlier, and warmth, comfort, rightness fill Shouto at his touch. With care, Katsuki sits back up, his mouth trailing kisses along Shouto’s check and neck, finally nipping at his chin.
“You’re mine,” he says. “My true mate.”
“There’s no such thing—” Shouto starts to protest, but as if in objection, the mark warms beneath his hand.
“I wouldn’t have believed it either,” Katsuki admits. “But it explains so much. I was always meant to love you because you were always meant for me.” He slides a hand into Shouto’s hair, stilling his head, holding him, his words tickling across Shouto’s lips. “And I was always meant for you.”
“I… I can’t… I don’t…”
“Don’t think, princess,” Katsuki murmurs. “Just feel. Let me take care of you.”
For a moment, panic and shock almost make Shouto try to pull away, but he can taste Katsuki’s desire building again, the scent of it spicy in the air. He forces himself to stop and breathe. He loves Katsuki, wanted to mate him more than almost anything in the world. Being true mates changes nothing.
“Okay?” Katsuki asks, pressing his forehead to Shouto’s.
Shouto meets his eyes, gives a tiny nod, then wraps his arms over Katsuki’s shoulders. “It’s surreal, but I love you. How could I be anything but pleased that you are my true mate?”
Grinning, Katsuki kisses him, his knot going down enough for him to rock his hips.
It is a long time before they finally sleep.
Showing the true mate marks to his father two days later is satisfying, but Shouto can’t help but be smug when they present the positive pregnancy test to his father on their one-month anniversary.
The reign of Endeavor over the Firestorm Group has ended; Bakugou Katsuki is the new boss, with his omega true mate, Todoroki Shouto at his side.