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Keith is a feral creature in his heat. Something about the mix of DNA makes him more vulnerable to his baser Galra instincts, which means that if Shiro wants to help him through it, he has to prove his worth as a stud.
They can usually tell when his heat is coming, because even as much of a wild card as Keith is day-to-day, he becomes more and more reckless the closer he is to his heat, and usually has to take time off from his duties day before his heat actually hits, which he hates. It makes him extra restless, and he’ll sometimes spend all day on the training decks, wiping new recruits across the mats.
Keith in motion, in the heat of a spare, is one of the most beautiful things Shiro has ever seen. He takes down Galra after Galra, regardless of rank, until Shiro finally grows tired of waiting.
He growls softly, and Keith whirls, eyes wild. He’s nearly there, nearly fully in heat. He growls in return, and Shiro gets to his feet, walking closer. There is energy in every cell of Keith’s body, eager and expectant, wanting. Neither of them are saying it, but in order for Shiro to prove his worth as a stud, he has to control his bitch, and once he has Keith under his control, he has to breed him up well, lasting long enough and coming sufficiently to appease the wild creature he is about to drag to his bed.
The recruits back away nervously as the two of them growl and scent the air, circling each other. Keith, more impatient than ever in his current state, lunges forward, teeth and claws bared. As strong and deadly as he is, he’s reckless, and though he can take out recruits, he’s no match for Shiro in this state.
Shiro bats him out of the way like a cat toy. Keith rolls, skids, and comes at him again, only to get knocked aside in a similar manner. He growls, and starts to circle, instead, trying to wait his alpha out. Their audience is rapt, some of them flushed, trying not to look as the smell of arousal fills the training deck, but looking anyway, especially when Keith dives in again with a yowl, only for Shiro to finally collect him, grappling him and then slamming him down onto the mats.
Keith bucks under him with a feral howl, but Shiro holds him down firm, panting, pressing his growing erection up against his bitch. The omega hisses, little mating coos escaping him. The observers around them start to respond with growls, rumbling in a needy chorus. Keith is strong, healthy and beautiful, and many of the other Galra in the room simply can’t stop themselves from calling out for him.
Counter to his level-headed nature, Shiro bares his teeth, snarls and snaps his jaw, the threat clear as he crouches over his omega and grinds down against him.
Keith is responding, arching and preening, delighting in Shiro’s possessive attention. Shiro can smell his slick hole, ready for breeding, seeking it here and now, but Shiro isn’t willing to share.
He growls again, and the others back down, but they eye him enviously as he picks up the trashing creature, tossing him over his shoulder and marching out of the room. Keith yowls, clawing at him irritably, annoyed he isn’t getting what he wants.
“Patience, my sweet,” Shiro coos, tone as soothing and soft as he can manage. He still has to tighten his grip to keep Keith from sliding away and looking for a new mate. Shiro can barely stand the rejection, has to remind himself that Keith doesn’t know any better. He gets them into their room, locks the door behind them and drops Keith onto the bed.
Keith doesn’t stay there for long, bolting for a corner to growl at Shiro threateningly as his alpha digs through their heat supplies. Finally, the pulls out reins and a bit. He knows he’s going to earn himself a few new bite marks wrangling his mate.
He approaches slowly at first, but when it looks like Keith is about ready to pounce, he moves first. He’s got less stamina, and he’s already wasted plenty, so Shiro manages to pin after only a few minutes of scuffling on the floor; but Keith plays a lot dirtier than him, and by the time he gets the bit in Keith’s mouth and clipped into place around the back of his head, he has a series of bites up his flesh arm from struggling to hold him in place.
Keith tries to twist away, and Shiro growls at him, then yanks on the reins and starts on his mate’s clothing, pulling it off quickly before tossing him back on the bed. He’s hard, bulging in his pants, and Keith stares at him, some of the fire in his eyes temporarily fading as he scents the air.
He purrs quietly, satisfaction slackening his expression as he drinks in the sight of Shiro’s dick. Shiro’s sure he’d be licking his lips if he could.
The alpha shucks off his clothes and then prowls closer, grabbing onto the reins again. He drags Keith closer, and lines up, shuddering when Keith’s response is a muffled mating call. Fuck.
Impatiently, Shiro starts pushing into him, watching as Keith’s soft pussy takes it all, stretching to accommodate Shiro’s thick cock. As a full-fledged Galra, and a particularly large one, the difference between them borders on absurd, but Keith’s sweet omega body was made to take it, and take it he does, clamping down and keening.
Shiro groans, having to still for a few moments before he can even think about moving without hurting his omega. He has to physically hold Keith down to stop him from moving right away. He’s grateful for the bit when Keith’s response to being denied is to lash out.
Shiro sighs and kisses the hollow of Keith’s throat. “I know, pet. Don’t worry. I’ll fill your little breeding hole soon enough.”
After a few minutes for adjustment, Shiro starts to move and Keith goes instantly limp, compliant now that his stud is giving him what he wants. Shiro’s sure he’ll get restless once his body starts craving a clutch, but for now, he’s blissful and beautiful, perfect under him.
“You’re so gorgeous,” Shiro tells him. Keith arches into him, not hearing the words, but hearing the tone, preening, knowing he’s pleasing his alpha. “A good little breeding bitch.”
Shiro growls, nuzzling into Keith’s neck, breathing in the stink of his pheromones. It makes his own instincts, deep buried preen, and he can feel himself twitching inside of Keith, feel his eggs getting ready, semen soaking them, dribbling out of him into Keith’s hole.
Keith moans, and when he bucks, there’s a distinctive squelch that makes Shiro’s thigh shake with anticipation. He growls, yanks on the reins to pull Keith’s head back, body arching, ass curving up to accommodate the pressure until Shiro can watch Keith’s pussy lips stretch to take him as he moves.
“Close, baby,” he breathes, the harsh sound of flesh on flesh between them as he keeps a tight grip on the reins in his flesh hand, holding himself up on the prosthetic. “Gonna breed you up.”
As soon as that first egg pushes past Keith’s stretched opening, he starts to get impatient again, whining, hungry for more.
The first one is the easiest. It slips in alongside Shiro’s cock with little resistance, his little breeding bitch’s sweet hole open and accommodating. It lands inside of his ready pussy along with a wet gush of precome.
The second, likewise, slips in without much fuss. It jostles the first, makes that sweet hole feel even tighter, the way a breeding hole should be. There’s another wet gush of slick, starting to drip out of Keith’s tiny hole now.
The third egg starts to push in, and that’s when Shiro’s sweet fuckhole groans in discomfort around the bit in his mouth and attempts to squirm away. Shiro tsks and pulls on the reins, forcing his squirming body right back into place as the third egg pushes out of his ovipositor and into Keith’s body. He’s already proven his worth as a stud, or Keith would surely be more offended by the rough behaviour. As things stand, he whines and waits to be bred up full and well.
“That’s only the third one, pet,” Shiro says, even though Keith can’t understand him in this state, and is deep enough in the throes of his instincts that he might not even be able to take comfort in the tone. “There are still three more.”
He has to yank on the reins again as the fourth one makes it way inside of the omega’s body. Keith is whining around the bit now, probably starting to feel the strain and stretch in his body. Shiro refuses to back out to make room for the egg, as much as he would like it. Once Keith has taken all of the eggs, he’ll have to take Shiro’s knot, and it’s easier this way.
“Shhh,” Shiro coos softly. The fifth is making its way out, and Keith is bucking in earnest now, eyes wide and urgent. “Shh, shh, my sweet bitch. It’s okay. You’ve taken it before. You can take it all. Don’t be scared.”
He nuzzles into Keith’s throat again, teeth nipping at the scent gland there. He drapes his body over top of Keith’s. It’s easier to keep him pinned this way, and the weight is a comfort to the frightened omega, who can now feel his stud all around him, warm and big, inside of him, filling him, and keeping him safe.
Keith stills, breathing vaguely uneven. He whines and stares up at Shiro with wet eyes as the fifth egg finally joins the others, slick gushing out of his stuffed hole.
It’s tight. It feels like there shouldn’t be any more room left inside, but Shiro knows that Keith’s body will stretch to take everything he has to lay inside of him. He reaches one hand down to feel the swell of his stomach, stretched to take the eggs inside of him.
“Just one more, baby,” he whispers. “Just one more, and then alpha can knot you, knock you up, breed you good.”
Keith’s shaking. He starts bucking again, and Shiro has to force him down, force his legs open as he pushes in the last egg, groaning as it slips free and his knot begins to swell. He has to nudge in a little further and Keith snarls, chomping at the bit, trying to get out of it, but he can’t, and then Shiro is snarling, he’s filling Keith up with his come, a flood that spills even with the knot. There’s just no room, and it spills all over the sheets, between their bodies, sticking to them, to the blankets.
Shiro slumps more fully down on top of Keith as he slowly recovers. Keith starts to purr, satisfied and lazy now that he’s gotten what he wanted.
The knot gradually goes down, more slick and come pouring onto the sheets. Shiro would be me concerned, but he’ll knot Keith plenty more times before the end of his heat. The omega is half-asleep under him, breathing deep and even. His hair is a mess, his body is covered in bruises and come.
Too lazy to do any proper clean up, Shiro slides down and uses his tongue to lick up most of their mess, tasting the salty combination of keith’s skin, his sweat, and his own come. He sucks a few marks into his soft thighs before sliding back up to pull blankets over them. They’ll have to wash them all later, but there’s no point until the heat’s over, so Shiro pulls Keith in close and gets comfortable.