Klaus is 13 when he presents at the dinner table.
He’s been feeling off for several days, a low-grade mixture of fatigue, abdominal pain, and diarrhea that has his father confining him to his room and the bathroom, unwilling to risk Klaus passing anything on to the rest of his siblings.
He doesn’t mind. Three days off training is like heaven. Klaus spends most of the time napping, listening to music, smoking weed, and daydreaming about that extremely hot fireman he saw at that last arson case they handled.
He’s feeling much better by the third night, well enough that Dad lets him come down to dinner with the rest of the family. He’s halfway through the meal (roast chicken, garlic mashed potatoes, and green beans), doing his best to tune out the nasal droning of Major something-or-other, describing how to field-strip an M16 rifle, when he feels a wave of warmth washing over him.
It creeps, moving up his body like sinking into a hot bath, before it settles into his bones. He puts his fork down, touching his cheek with the back of his hand. It’s hot to the touch.
He can feel something happening in his lap as well, a spreading heat that turns into a dampness that panics him. For a second, he’s worried he’s shit himself. There’s no smell of feces, however, just a bizarre leaking sensation. Ben nudges him, below the table, face concerned. Klaus wonders how flushed he looks.
“M-may I be excused?” He asks, head bent. He doesn’t know what is happening, but whatever it is, he doesn’t want it happening at the dinner table, in front of Dad and Luther and everybody else.
His father looks at him sharply, displeased at the rule-breaking, but something in what he sees must be cause for concern because he doesn’t snap at Klaus for speaking. Instead, he stares at Klaus for a long, uncomfortable moment, before his eyes close and his nostrils flare briefly.
“Grace, Pogo,” he says sharply, like he says everything, “get Number Four to the suite.”
“What’s wrong with Klaus?” Ben asks, getting to his feet as Mom and Pogo come over and help Klaus up. “What are you—”
“Silence, Number Six!” Reginald barks, stare so intense that Ben sits back down, head dropping. “This is none of your concern.”
Klaus stumbles as they lead him out of the room, legs feeling like jelly, and he barely glances back in time to see his siblings watching him with concern as he’s led away.
He doesn’t have many clear memories following that, just heat and fear and a desperate sense of arousal and loneliness, so strong it makes him scream and claw at the locked door of the set of rooms. These are rooms he’s never seen before, deep in an unused corner of the sprawling academy. He’s so alone. Some animal part of him knows it’s wrong, that he shouldn’t be alone, so he cries for his father, for his siblings, for anyone, until his voice is gone. He scratches at the door until his fingernails are broken and bloody.
He’s so empty, begging to be filled in a way he doesn’t understand, wet and hot and hollow.
Klaus is barely conscious when the storm of heat over him breaks, leaves him shaking and wrung-out, dehydrated and sore, curled into a miserable ball on the bed’s disgusting sheets. He clings to his mother when she comes in, uncaring that his filth gets all over her nice clothes. She strokes his sweaty hair, humming softly as she encourages him to drink a little lukewarm water.
“How long?” he croaks out, each word feeling like shards of glass in his throat. He can’t stop shivering. He feels like an exposed nerve.
“Three days,” Grace chirps, smoothing his hair back. He desperately needs a bath.
“What…” he swallows, ignoring the pain that causes, drinks another sip of water. “What’s wrong with me?”
“Nothing’s wrong,” Grace says. “You’re just—”
“You are an omega, Number Four,” his father says, appearing in the doorway from the darkness of the hall. “You have presented.”
Dad had given them “The Talk” a couple of years ago, a strange mix of flowery, archaic terms and brutal, clinical examples that had left all seven children mostly confused about what it all meant. But Klaus remembers enough.
“I’m going to have a baby?” he yelps, attempting to sit up in surprise. His weak, shaky limbs refuse to hold him and he collapses back into Grace’s lap.
“No, silly, you can’t have a baby by yourself,” Grace says. “This just means your body can have a baby someday.”
His father says nothing, just studies Klaus, like he is an experiment. Klaus wants to shrink away from that cold gaze, but he holds himself still. Running always just makes things worse.
“Take him and clean him up,” Reginald orders. “A day of rest tomorrow, then training resumes.” He turns on his heel and leaves as silently as he arrived.
Klaus expects things to be awkward when he returns to training, but someone must have lectured the others beforehand because no one says anything. They just cast curious glances his way when their father’s back is turned.
Ben shyly asks him about the experience that night after lights out, and his father calls him to the infirmary the following day and gives him an injection, but otherwise things go back to normal for almost two months.
They’re wrestling, one of Klaus’ least favorite training sessions. He loses to everyone and it always ends up with Luther and Diego fighting and Diego crying into Grace’s apron later in the kitchen.
He almost has Allison pinned when she whispers in his ear, “I heard a rumor you gave up and let me win” and he feels his limbs go weak. She pins him, crowing in triumph.
“Come on, that’s cheating,” he grumbles from the floor, panting.
“I adapted,” she says smugly, but she does help him to his feet, so he can’t really hold a grudge. If his stupid powers could help him beat the others in training, he’d probably use them too.
“Switch partners,” Reginald orders, standing to the side of the training room. His dutiful shadow Vanya lurks next to him, clutching a pad of paper and a pen, hair in her face.
He gets Luther next, which at least means a quick loss and a chance to rest. Luther never holds back, and any bruises or sore muscles he gets from his loss will be worth the break while the others struggle.
He’s right. Luther takes him down brutally, and efficiently, after Vanya blows the whistle. He thumps Klaus down on the mat within seconds, pinning him.
Only, Luther doesn’t climb off after his win, doesn’t smile in triumph or scold Klaus for his technique. Luther stares down at him, eyes dark, fingers tightening around Klaus’ wrists and his breath coming in harsh bursts.
“Luther? You won. Let me up.”
Luther doesn’t respond, just keeps staring, breathing deeply through his nose before leaning down to press his face against the hollow of Klaus’ throat. There’s a strange pressure against Klaus’ hip that he realizes is Luther’s erection.
“Luther, what—” He struggles a little, tries to pull his arms free, and Luther growls at him like a dog, teeth clenched together.
“Number One!” Reginald barks, and usually Luther would leap to respond like the loyal hound he is, but he ignores their father, licks Klaus’ throat and rocks his hips. There’s a strange scent in the air, musky and spicy, that Klaus has never smelled before. He’s horrified to realize he can feel the beginnings of dampness between his legs, small licks of fire building in his belly.
“Number One!” Reginald shouts again, but Luther is too far gone and Klaus can feel himself slipping along with him. He sees their father bark an order to Vanya and her scurry out of the room, but all he can focus on is the smell of Luther, the way he’s pressing Klaus into the mat, his wet mouth and sharp teeth at his tender throat. Klaus arches his back, lifts his hips up to meet Luther’s body.
Luther is torn from him roughly and Klaus whines at the loss, moans as Luther’s snarling, spitting body is restrained by Diego and Five. Ben and Allison are holding Klaus, preventing him from reaching out to Luther.
“Stop, stop,” Ben whispers in Klaus’ ear, but Klaus doesn’t care, he needs Luther and they’re ruining everything.
Mother comes in, holding a syringe, and Klaus sees Diego look away quickly to avoid swooning as she injects the clear liquid into Luther. Luther sags almost immediately, eyes hazy, mouth slack.
“Number Two, Number Five, get Number One to the suite,” Reginald orders, cane grasped in a furious, white-knuckled grip. “That sedative will not last long.” He glances at Klaus, being cradled by Ben and Allison, keening for Luther. “Bring Number Four as well.”
Klaus loses time as they bring him and Luther to the suite of rooms he suffered in only two months previously. He blinks and they’re there, Ben and Allison helping him lie on the bed as Luther is deposited next to him.
“No,” he moans, trying to stand. He remembers little of his time here, but enough to know he doesn’t want a repeat.
His siblings look torn. Their father orders them back to practice, closing the door behind them and turning to face Klaus. “You are an omega, Number Four,” he says. “Do you know what that means?”
Klaus shakes his head, covering his face with his hands. The seat of his workout pants and the briefs beneath are soggy, uncomfortable, but he’s not about to strip them off in front of his father. His heat is building, slow and sluggish with the absence of Luther, but it’s coming and he’s not sure how much longer he can hold onto himself.
“Number One has presented as an alpha. That means he needs an omega to assist him through his rut. You must be that omega, for the good of the team,” Reginald says, voice brooking no argument.
Klaus can’t speak, words caught in his throat. His father leaves without another word, locking the door behind him.
Klaus rolls over and presses his face to Luther’s shoulder, the familiar smell of him both a comfort and a torment. His heat, now with no conflicting scents in the room, is back to building at a fever pitch and he whines behind his teeth. His hands, acting as if without orders, begin to strip off his workout suit, shoving the wet track bottoms off, tugging the soggy briefs off with them. He’s so hot.
It’s not long before Luther stirs, rut and his own preternatural strength burning off the sedative at lightning speed. He groans, clutching his head before the scent and sounds of Klaus seem to reach him and he bolts upright, whipping his head around to face the heat-stricken omega on the bed next to him.
Klaus has gotten his workout jacket off and is struggling with his shirt, his last remaining piece of clothing, when Luther looms over him. He settles himself between Klaus’ legs, grabs his wrists with one hand, pinning him to the bed, and grabs the front of Klaus’ t-shirt with the other.
Luther presses his face to Klaus’ throat, resuming where he left off in the training room. He rolls his hips, pressing his clothed erection into the cleft of Klaus’ ass, and Klaus sobs, heat blooming in him like a wildfire.
“Please,” he gasps, not sure if he’s asking Luther to stop or continue. Maybe both. “Please.”
Luther bites at his throat and rips the shirt from Klaus when it gets in his way. It stings a little, the discomfort immediately swallowed by the wave of sensation as Luther moves his attention to Klaus’ chest, then his belly, then lower.
Klaus has never even kissed another person, let alone anything like this, and he’s overwhelmed, lost in Luther’s mouth on him, in him.
Luther fumbles with his own clothing, tearing it in his haste, and then he’s back on Klaus, hiking his hips up. He presses into Klaus and everything fades away in a wave of heat and pleasure.
After, when their urges are fulfilled — at least for now — Luther runs a bath and helps Klaus into it, climbing in after him. They each take an end, sitting with their legs pressed together.
Klaus is still shivering, coming down from the high of his orgasm. He can’t focus and drops the washcloth several times before Luther takes it from him.
“Are you okay?” Luther asks, voice hoarse. “Did I—” He looks away, shame coloring his face. “Did I hurt you?”
“Mm,” Klaus hums, letting his head loll back against the rim of the tub. “Dunno.” He doesn’t think so, but everything is so floaty right now.
“I’m sorry,” Luther says, and he sounds so close to crying it breaks through Klaus’ afterglow. He lifts his head back up and, despite Luther having his head turned away, he can see the tears in Luther’s eyes.
“What for?” Klaus asks. Sure, the bite stings, but he feels amazing, better than weed. He hasn’t seen a ghost in hours. Maybe the smell pushes them away.
“I should have been stronger, I should have— resisted, or something,” Luther says, voice soft and agonized. Klaus sighs.
“Luther, you’re an alpha. You couldn’t help it.” Klaus shrugs, trailing his hand through the water. There are bruises blooming on his wrists, his hips. The claiming bite, where his neck meets his shoulder, throbs. It probably needs to be bandaged. He smiles, hoping for comforting, but he’s pretty sure he misses the mark. “I’m an omega. This is what I’m for. At least I finally have some use to the team.”
“Don’t say that,” Luther says fiercely, sitting up so fast he sloshes water of the rim of the tub.
“Why not? I mean, my powers aren’t useful and I can’t fight. At least I can do this.” This is their father talking, and Klaus hates it, but he can’t stop himself from parroting Reginald’s words. After all, he’s not wrong.
“Don’t talk about yourself like that. You’re my brother. You’re part of the Academy. You’re not just…”
“A hole to breed?” Klaus says waspishly, crudely, and Luther flushes, but nods.
It’s stupid, but it makes something unclench inside of Klaus, spreads a warmth inside of him. It’s nice. “I’m sorry it was me,” he says.
Luther’s brow furls. “What do you mean?”
Now it’s Klaus’ turn to look away. “I’m sorry it was me, and not Allison.”
“Oh,” Luther says, sounding like the air got punched out of him. “Yeah. Um. It’s, it’s fine.” He clears his throat awkwardly. “I mean, if it couldn’t be her… I’m glad it’s you.”
There’s that warm feeling again.
“Well, it could be worse,” Klaus says. “It could have been Diego instead of me.”
“Oh god,” Luther says, barking out a laugh. He leans back against the tub again, eyes crinkling with laughter. It’s a good look on him, Klaus thinks, better than the stern Number One face he puts on most of the time. “God no.”
Klaus doesn’t think he’s ever seen Luther this soft and open. Maybe he’s like this with Allison in private, but that’s a very privileged club to be part of, he thinks, and smiles to himself.
Their heat-rut cycle burns itself out about 36 hours later. Klaus can feel the last wisps of heat fading as Luther has him on his back, legs over Luther’s shoulders. He can tell it’s fading for Luther as well, who is less frantic, rutting animal as he fucks Klaus, kissing instead of biting, holding him close instead of pinning him down. It’s nice, and Klaus clings to Luther as he comes, shaking with more than just exhaustion and orgasm.
Luther stays pressed flush to Klaus’ body, cradling him, breathing in the scent of Klaus’ hair. It gets uncomfortable after a couple of minutes, though, and he shifts upright, pulling Klaus into his lap to wait for the knot to shrink.
Klaus slumps against Luther, bone-tired, emotionally drained, confident that Luther will keep him cradled close. With the heat fully gone he can feel how sore he is, how grimy his skin feels, the hunger snarling in his belly.
“I could eat a horse,” he mumbles against Luther’s neck, and Luther huffs out a tired laugh.
“Me too,” Luther sighs, bringing one hand up to stroke Klaus’ sweaty back. “I miss my bed.”
“God, yes,” Klaus grumbles. “I want a nap, away from you.” He pauses, kisses Luther’s shoulder in apology. “No offense.”
“None taken, I’m ready to be away from you too.”
Klaus laughs in relief. He’s tired, sore, filthy and he knows he’s going to have some sort of freak out about this later, in the privacy of his own room, but he came out the other side of this mess in one piece.
“Thank you,” he says, and he means it.
Luther makes a curious noise. “For what?”
“My first time alone was horrible. I was so scared. It hurt so much. But this time was so much better. So… thanks.”
He’s never been this emotionally open with Luther before and it scares him, that Luther will revert back to his usual self now that the hormones are gone, or tease him. But Luther just gives him a little squeeze.
“I’m glad.” He lets go, pulls back so he can see Klaus’ face. “You won’t have to go through it alone again, I promise.”
Things aren’t radically different after they bond. Luther is still a suck-up to their father, still follows his orders, the same old bossy Number One. He still moons after Allison, sneaking off with her when they think no one is looking. Klaus is still Klaus, still mostly useless at his powers and in training.
But Luther is softer with him now. Not soft, not indulgent, but softer. He smiles at Klaus’ antics more, is less annoyed and more concerned when Klaus comes to training or the dinner table stoned. He touches Klaus sometimes, passing him in the hall or during schoolwork, gentle fingers on the bare skin of his wrist or knee.
Once, memorably, he touches Klaus under his shirt in the bathroom. Luther’s calloused fingers stroke his sides and belly, thumbing at his nipples, lips and teeth at his mouth and throat. It goes on for several minutes before a sound from outside spooks him and Luther withdraws, face burning. He storms out of the bathroom and Klaus is left speechless, cheeks flushed, mouth red and wet, dick hardening in his shorts.
For the most part, his dynamic doesn’t come into play much, especially not during missions. Sure, he’s the lookout, but he was the lookout before he was an omega. He doesn’t take it personally.
During one mission, a simple bank robbery, Klaus is caught off-guard by one of the robbers.
The man is an alpha, reeks of it, and to Klaus’ surprise, is apparently so distracted by finding a lone omega that he puts away his gun and instead decides to paw at Klaus. It’s weird and disconcerting, but gives Klaus the chance to overpower the creep, knocking him out with the kind of perfect form he can never manage to pull off in training.
“I finally do it, and no one’s here to see it,” he gripes, kicking the robber’s gun away.
Klaus doesn’t have anything else, so he uses his tie and the robber’s belt to bind his hands behind his back and waits for his siblings to find him.
Ben, as usual, is soaked in blood and viscera, but offers Klaus a thumbs-up, which is nice, and Reginald tells him he did an adequate job, which is high praise considering the kind of feedback he usually gets.
Luther, however, is quiet after the mission. He skips his usual seat in the car next to Allison in favor of sitting next to Klaus. This displaces Ben, who gives Luther an annoyed look before buckling in next to Allison.
Luther casually drapes his arm behind Klaus’ shoulders, which is a weird enough move that all their siblings, including Klaus himself, are giving Luther the side-eye, but Luther just stares out the window, hand pressed against the back of Klaus’ neck. His fingers are resting against the bite mark. It must be some kind of alpha bullshit, Klaus concludes. He spends the ride back to the academy sitting stiffly, not wanting to scare Luther off but not wanting to openly sink into his touch. That’s something they’ve both been avoiding.
They debrief with their father when they get home and Luther is visibly antsy, eyes straying to Klaus whenever Reginald isn’t looking. When they’re dismissed upstairs to change, Luther corrals Klaus into his room before Klaus can protest.
“Take it off,” Luther snaps, tugging at Klaus’ uniform zipper. Klaus catches Luther’s hand.
“What the hell are you doing?” he asks. Luther is flushed, anger simmering, sweat beading on his upper lip. “Are you okay?”
“Take it off, Klaus, get it off!” Luther yanks the zipper down so hard Klaus is pretty sure he’s broken it. “You smell like him.”
Oh, Klaus thinks. He stops struggling, lets Luther strip the leather suit from his shoulders. The undershirt he’s wearing underneath is sweaty and the shock of cool air feels good.
Luther seems content enough once the uniform is hanging loose around Klaus’ waist, drawing Klaus into his arms. He presses his face into Klaus’ neck, rubbing his sweat and scent onto the exposed skin.
“Gross,” Klaus complains, but he tolerates it. Luther is usually extremely good about keeping his alpha bullshit to a minimum, so this must be serious.
Luther stops after a bit, breathing slowly and deeply. It’s weird how normal this whole situation is. Unlike the incident in the bathroom, which left Klaus desperately jerking off on the toilet before he could join his siblings for lunch, this is… soothing. Comforting. Quiet.