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Katsuki kicks the door open with his foot, and neither of them flinch — if anything, Eijirou only purrs louder.
“Mm, welcome back Kacchan,” Izuku mumbles, happy, but distracted. He’s grooming Eijirou again, working a thin brush under a particularly stubborn scale and slowly prying it free. So gentle in his inhuman strength, it’s relieved sighs all around when he succeeds – Eijirou’s been whining over that one for weeks. Katsuki swallows his impatience in favor of watching him work.
It was the last one. Izuku smooths over Eijirou’s back, scratches around the thick lining at his nape, and Eijirou’s tail thumps contentedly.
Eyes sparkling, Izuku smothers his laugh into his arm. Maybe once upon a time Katsuki would’ve stomped around, grumbling and slamming things and generally making a fuss to reclaim his attention, but Katsuki can admit by now in the privacy of his own mind that he finds Eijirou’s helpless reactions just as endearing (though Izuku probably knows, perceptive little bastard).
Izuku finally — finally — looks up to assess his haul, and he lets this hunt’s game drop with the tension in his shoulders.
“Kacchan,” Izuku scolds, but Katsuki was careful enough, and the room quickly fills with the low hum of his muttering. He checks the teeth, the eyes, the hooves and the weapons tucked under the paws. The soft, satisfied sounds he makes as he finds them all intact have Katsuki’s chest swelling with pride. He would’ve done better with Eijirou there, but he knows what the hell he’s doing.
Eijirou chirps, snuffling curiously around the feet of a rabbit, and Katsuki clicks his tongue in warning. “Easy. Deku first, you know that.”
Eijirou cowers, head tipped in shame, and Izuku scratches absently behind his horns. “You can have the entrails, Kiri,” he soothes, and that rumbling in Eijirou’s chest starts up again. It’s calming, the combined noises they make, heard from all corners of their home — but Katsuki will take that thought to his grave.
He feels a flash of guilt all over again for not taking Eijirou with him on the hunt, but he’s been too rough with the animals recently. Nonverbal for days now, all bared teeth and instinct, the last carcass he brought back to Izuku was so chipped and mangled they couldn’t save a thing but the meat.
Under normal circumstances, the knowledge that Eijirou can keep Izuku company while he’s out would be – comforting. Izuku can’t take care of himself for shit, and half the time he forgets to eat if Katsuki doesn’t drag him out of his lab himself. Eijirou’s always been good at reminding him when Katsuki can’t – he doesn’t do well skipping meals, and he’d never eat without them if he can help it. It’s a pack thing and also a concern for Izuku’s wellbeing, which Katsuki appreciates.
It’s not that he’s afraid to leave them together now, with how Eijirou’s been, but he thinks it’s pretty fucking reasonable to be concerned when your shifter best friend goes mute and starts losing the shit that makes him human. And – okay, maybe he misses his partner. Screw him, it feels good to have someone watching your back.
He hasn’t said it out loud yet, but Katsuki can tell by the marks on Izuku’s lower lip — not his, for once — that he’s just as worried.
Eijirou’s been hoarding the furs, too — they usually barter those, or refresh their bedding if needed, but Izuku almost lost an eardrum the last time he tried. Katsuki had to come back to him sobbing, not over himself, but the sound Eijirou made when he started to bundle them up. It was terrifying.
He won’t let that happen again. Eijirou whines in his throat — still no words — and Katsuki rolls his eyes through the spike of concern because someone has to keep their head around here, and it’s not gonna be the mage with no self preservation instincts whatsoever. The braindead dragon is out of the question.
“Yeah, yeah, I’ll skin ‘em for you in a minute, Red, relax.”
This settles him. Eijirou makes a pleased sound and shuffles off to the bedroom – probably to fuss with the furs next to Katsuki and Izuku’s bed again. Last night he rustled around for a solid hour, humming and shoving things to the side, then back to the middle again, growing increasingly frustrated with their arrangement. He refused to calm down until Izuku flung a hand over the side and rubbed over his jaw, and Katsuki snapped at him to just come up.
Sleeping with a dragon shifter on the chest is rough, he’ll admit, but better than jolting awake because he’s whining over bear pelts again.
Katsuki hauls up what he can for skinning, and Izuku follows closely behind. He can practically hear the anxiety in his footsteps, imagine so clearly the lower lip pulled between his teeth even as Katsuki lowers the carcasses on the table. He straightens, and Izuku slips his arms around his waist, face tucked between his shoulder blades.
Katsuki’s body betrays him with the speed at which it relaxes, like Izuku’s touch is an off button for his racing thoughts. Izuku hums as he feels it, like he knew it would be, which — he probably did.
He‘s always aware of just how deeply things affect Katsuki, even if Katsuki doesn’t realize it himself, and this has been – a lot. Eijirou’s been by their side since before Katsuki could so much as hold a bow, imprinted on the two of them as toddlers, and they’ve never experienced anything like this from him. No amount of lessons on dragon culture prepared them for this behavior, and asking Eijirou to explain himself isn’t an option when he hasn’t been speaking. Katsuki tangles their fingers together at his front and squeezes, and Izuku’s hold tightens.
They were raised together, he and Izuku, bonded since they were of age, and Katsuki still struggles to come to him for comfort – not out of hesitation, but a lack of impulse. He finds himself grateful, once again, for Izuku’s unfailing tendency to seek him out.
They breathe in and out, deep, and it’s steadying.
“Tell me.”
“He brought another bird back,” Izuku whispers, muffled. “Tried to drop it in our bed. I had to pick the feathers out of his teeth.”
It’s the third time this week. Katsuki curses under his breath. “What else.”
“He snapped at the wolves. Wouldn’t let them greet me. They looked so sad, Kacchan.” He says it all mournful, and Katsuki hates that every piece of this is something for Izuku to worry about. The birds, the wolves, everyone’s feelings but his – Eijirou could hurt him and he’d find a way to make it his own fault. Katsuki can chew him out for it until his throat hurts, but Eijirou is still better at gently reminding him to take himself into consideration every once in awhile.
He can’t ask for Eijirou’s help for this. A part of his team is down for the count, and he’s starting to feel so lost.
“I’ve done all the research I could about imprinting, but so much is word-of-mouth, Kacchan. I — I don’t know what’s wrong.”
The devastation, the helplessness in Izuku’s voice yanks at Katsuki’s heartstrings something awful. This man and his tendency to treat the problems of the world as his own. It used to piss Katsuki off, but now it just aches. He turns in Izuku’s arms and pulls him snug, burying his face in his curls and rubbing firmly up his back.
“Hey,” Katsuki chides, commanding but soft. “This isn’t all on you. We’ll figure it out.”
“I know, I just –”
Izuku pulls back and scrubs at his eyes, face wet, and Katsuki finds himself angry at the world all over again. How cruel it is, to put the people he cares about most through hell and back, time after time.
No rest for the wicked, everyone says. Katsuki would argue otherwise. How soundly they’d sleep if they all could care a little less.
Izuku opens his mouth, twisted in grief, and is cut off by claws scrambling over the hardwood.
Katsuki doesn’t know what to make of the timing.
There’s a clatter, a huff, and Katsuki looks up to find Eijirou in the doorway, jaw slack. All ruffled scales and wetted lips, hair a shock around his horns — there’s a wild look in his eyes that would be alarming if not for the prominent crow’s feet at the corners.
Katsuki’s necklace lies in tangles on the hardwood, coated in saliva. Izuku extracts himself and takes a step forward, then blinks as Eijirou crouches, teeth bared, pupils blown.
His growl is playful but startling – familiar in tone but foreign in depth, a sound Katsuki hasn’t heard since Eijirou was much younger.
“Ei,” Katsuki starts, and Eijirou snatches the jewelry again and is gone, tail slamming into the doorframe in his enthusiasm. Despite the situation, Katsuki’s amusement leaves him in a huff.
Izuku’s mouth is ticked up but tight around the corners, and he’s quick to follow, tears forgotten, laugh wet. Katsuki shuts the door tight behind him and does the same.
Eijirou’s fast, but his trail is obvious. He’s tipped over the poker by the fireplace, left various feathers and strands of fur in his wake.
“Shit,” Katsuki mutters.
Up the stairs and around the corner, they pick up the pace, hearts racing, but he’s there. The beads lie abandoned in the doorway of their bedroom, and they find Eijirou amidst disaster. He’s upended his fur pile entirely, integrated into their own on their bed, and he sits in the center of it all, panting.
Ah.
Katsuki’s chest has been ruffled through carelessly, jewelry and capes strung out over the floor. He’s suddenly grateful Izuku’s study is locked — doesn’t want to imagine the disaster if Eijirou got into his any of his potions.
Eijirou makes a sharp sound in his throat, brows pulled low, and Izuku takes a cautious step forward and gasps.
“Oh — Kacchan, he’s —”
Naked, Izuku doesn’t finish, because Katsuki can see for himself. Naked, and wet, and dripping onto the pelts. Arousal a vibrant flush down his chest, the colors of his scales are only amplified under the heat. Eijirou’s claws flex in the bedding, and the furs give like parchment, tearing easily under his strength. Eijirou blinks like he’s shocked at himself, and they retract.
The wide-eyed, terrified expression he wears twists Katsuki’s heart up to his throat. Eijirou doesn’t look like that. He doesn’t make that face, and it only amplifies every wrong feeling Katsuki has felt since his symptoms started.
But Katsuki knows what a dragon in rut looks like. Eijirou’s so hard it looks painful, swollen at the base and drooling down the length. And when Izuku gasps, “Oh, Kiri, does it hurt?”, it confirms every one of his suspicions.
The hoarding, the guarding, the aggression — it all clicks. Katsuki stands dumbfounded, because this is more than just seasonal biology taking its toll. It means something.
Ruts only come around mates, which means Eijirou’s body thinks they’re —
Oh.
Eijirou nods, shaky, and Izuku exhales, scrubbing a hand over his cheek. He looks sideways at Katsuki, and Katsuki can read this man like lines of ink. He knows what he’s gonna ask even before he does, and his chest swells through an uncomfortably overwhelming onslaught of anticipation and affection.
When this is all over, he’s gonna tear Eijirou a new one for not telling them about this, unpredicted or not. Going into rut, scaring the shit out of them – it’s a hell of a confession.
But it isn’t unwelcome. Katsuki always knew it’d be the three of them for life, and he and Izuku had been discussing it for ages now, pillow talk in the dead of night when Eijirou had slipped out to stretch his wings. A question they weren’t yet brave enough to ask, despite their history.
Of course Eijirou would beat them to it. Over-eager bastard.
Izuku opens his mouth, and all the needlessly cautious looks are starting to make Katsuki’s head pound, so he says, “Gonna be a bitch to clean all this up when we’re done.”
Izuku’s jaw closes with a click, and he beams. He runs his knuckles down Katsuki’s arm, glides his tongue over his teeth. “Do you think your haul today will be enough?”
They’ll be fine for a few more days — Katsuki admittedly went a little overboard in his quest to prove — what, he doesn’t know. That he could do things himself. That they might need Eijirou, but Katsuki could still take care of them when things get fucked up. Like he’d done when Eijirou’s wings grew in fully, and he spent weeks laid up from the pain. Like when Izuku was still learning and his spells would backfire, and Katsuki would hunt a little extra to trade for supplies. Like he has every time they’ve needed him. Like he’s been doing. Like he’ll continue to do now.
There’s nothing to think about. Katsuki nods, and Eijirou whimpers. Izuku coos, and the sound loses its fear.
“Oh, honey,” Izuku shifts, plants one knee in the nest. At Eijirou’s visible relief, scales smoothing out, wings drooping, he crawls closer, accepting the nosing into his chest, the drag of Eijirou’s cheek over the crook of his neck.
Eijirou blinks up at him, eyes lidded, and Izuku kisses him.
Katsuki’s stomach bottoms out in one fell swoop.
Eijirou’s not gentle with his teeth, and Izuku preens under it, a choked laugh-turned-gasp tearing from his throat as Eijirou drags them along the curve of his jaw. The sight of them is like a gravitational pull, and Katsuki’s in the nest with them before he’s told his body to move, thumbing at the bony protrusions poking out of Eijirou’s forehead.
They’re sensitive, and Eijirou pulls back to gasp.
Clawed fingers dig into his thighs, miles away from full strength, and it stings a little, but that just makes the warmth in Katsuki’s belly burn hotter. Eijirou tips his head to scent Katsuki thoroughly, and the purring starts, loud and echoing in his ears, a sound so low it vibrates his teeth.
“Oi, bastard, watch the horns — someone’s gonna lose an eye, goddamn.”
Eijirou huffs, catching Katsuki’s wrist and rubbing it over his neck, and Izuku reaches out to do the same, looking delighted when Eijirou shakes. Eijirou chirps a sound, high and wholly unfamiliar, and a sharp joy sings in Katsuki’s veins. It feels — like the frequency is meant for him. For them.
Izuku sniffles, eyes big and soft and glassy. He pets over Eijirou’s lower belly, and Eijirou’s chest rumbles so loudly and forcefully Izuku’s hands shake where they touch.
“Oh, I can’t believe — all these years, we could’ve —”
Izuku cuts himself off by sinking his teeth into Eijirou’s neck, like a reflex, like possession, and the sound Eijirou makes is inhumanly pleased. All the hair on Katsuki’s body stands on end, arousal kicking hard in his gut, and Eijirou’s eyes flutter closed, lashes stark crimson, wings and scales catching the sunlight through the open window.
He’s beautiful.
“Mate,” he sighs, painfully affectionate, and that tight thing in Katsuki’s chest finally loosens.