At sixteen, Kaeya was considered more than just a late bloomer, he was almost guaranteed to be a beta with how long his presentation had taken to arrive. Diluc had known what he’d been since he’d been 12, an Alpha, every bit the mirror image of his father, striking a gentle, yet commanding presence everywhere he went. With his wide eyed smile, and soft, fluffy hair, Kaeya always joked that he had been better suited to be an omega, however in training, there was no question about his status.
Already somewhat of an outsider, Kaeya didn’t necessarily mind that he didn’t know what he was supposed to be. His demeanor wouldn’t have changed even if he’d presented on time, and considering he was already a ward of the Ragnvindr’s, he had a relatively comfortable life, having had the best upbringing that they could afford.
Even being an Alpha wouldn’t have boosted his social status any further.
“Kaeya, are you going to hurry up or do I need to go over there and grab your weapon myself?”
Diluc was already pacing the training yard, twirling his sword around as he waited for Kaeya.
He’d changed into his training gear in a blink of an eye, eager to start their daily sparring session.
Out of all the staff, Diluc exclusively trained with Kaeya, using the excuse that nobody else could keep up with him. While that might have been true, and it seemed to be, the reason at the end of the day was simply that they enjoyed their time together a little more than was probably acceptable.
They’d grown up together for years, and even Kaeya knew that they had some sort of attraction to each other, always skirting around their unspoken desires.
Even in his wrinkled shirt and dirty training trousers, Diluc was undoubtedly the most attractive person Kaeya had ever met. Not that he’d tell him. And maybe, if one day he had the opportunity, and Diluc wasn’t married to some rich merchant’s daughter, he’d drag his unfortunate beta ass to the Alpha and ask to be mates.
“You should, I’m tired of being the only one grabbing it.”
Kaeya tossed back the comment, his lips twitching up as he saw Diluc’s cheeks turn pink.
“Don’t be disgusting! Hurry up, I want to go down to the lake afterwards.”
“I didn’t say anything wrong.”
Kaeya finished lacing his boots up, grabbing his dull, practice sword and joined Diluc in the ring.
It was one of the most unfortunate setups, but Crepus had explained that being in the direct heat, with the loose dirt, provided a good practice for battle. Even if it provided a more realistic experience, the day was already unbearably hot, with Kaeya’s white shirt sticking to his back as little drops of sweat beaded down along his skin. If they’d only had an indoor practice area, training would be slightly less unbearable.
“You know, we are probably the only ones practicing every day.”
Kaeya wasn’t a slacker, but he didn’t put in as much effort as Diluc did into being the best. However, Diluc was supposed to be the example, always eager to please his father.
“And? That’s why we are the best.”
“You mean that’s why you’re the best. You need to get another volunteer to beat up Diluc.”
That whole week Kaeya had become less and less interested in practicing, which he’d attributed to the incoming summer months making him want to laze around, and even standing in front of Diluc he didn’t have the desire to fight at all, twirling the sword in his hand as he half heartedly got into position.
In contrast, the Alpha already seemed worked up, pacing around impatiently as he looked at Kaeya, planting his feet firmly in the dirt.
Typical of an Alpha, eager for a fight.
“I’ll go easy on you Kaeya. Best out of three rounds.”
“Deal. And then you can get us something cold to drink.”
Diluc waved his hand, brushing away Kaeya’s words, counting down before initiating their sparring session.
Like usual, he waited for Kaeya to swing first, dodging around him, making his hair smack Kaeya in the face. It was a little jab at Kaeya. Even if Diluc was being serious they couldn’t resist teasing each other during training, during practice, during any of their conversations. It could even be taken as flirting, with how nice the Alpha’s hair had smelled.
Each movement took concentration, even more than normal, as Kaeya worked to keep up, avoiding Diluc’s quick, firm swings.
It almost felt like he was being toyed with, Diluc clearly avoiding some openings he gave to drag on the round, his pupils dilated as he watched him, getting in closer than normal, getting into Kaeya’s space each time he knocked his sword out of the way, easily pushing any blows that Kaeya tried to land off to the side.
He felt sluggish, his whole body fighting him with each step as he wiped his bangs away from his face, the sweat having made his hair stick to his forehead.
In one swift movement, Diluc knocked his sword out of his hand, shocking Kaeya out of his distracted haze as it clattered on the ground.
“Are you even trying Kaeya?”
“Are you even trying Master Diluc?”
Kaeya couldn’t think of anything better to say, grabbing his sword from the ground as he glanced at him from the corner of his eye.
“You could have easily ended that sooner.”
“I’m making you work since I know you can do better.”
Diluc seemed to be growing impatient with him, pointing his sword at Kaeya, barely giving him a minute to recover.
“Again. I won’t go easy on you if you’re not trying.”
“I get it, I get it, calm down..”
Kaeya undid the strings at the top of his shirt, leaving them dangling, hoping to get at least a little bit more fresh air on his skin. It wasn’t just him who seemed to be affected by the heat. Even Diluc’s cheeks were showing splotches of red, and his shirt seemed to be equally drenched.
“Round two..” Kaeya half muttered, swinging forward, trying to grab Diluc unaware before he could count down.
He didn’t take him by surprise, but it seemed to be what Diluc was looking for, smirking back at Kaeya as he blocked him, inches away from his face. They were close, with Kaeya pressing forward, the blade grinding against Dilucs. His scent was stronger than ever now that he was close to him.
It had always been a presence around Kaeya, a dull, comforting scent, vaguely discernable from all the other scents of the staff.
It wasn’t any longer.
As clear as day the scent of cedar pines hit Kaeya, almost as fast as Diluc’s sword did, knocking him back onto the ground. His head didn’t hit the floor, but his sword slid far away from him as Diluc pushed his own blade against Kaeya’s neck.
“You didn’t even try that time.”
His hand was shaking, and even if the dull blade was only managing to apply pressure to his neck, Kaeya was still concerned, piecing together what had happened.
“I need to go- Diluc-”
“You’re not leaving. We aren’t done.”
Diluc took a step forward, placing his foot on Kaeya’s chest, dirt smearing across his shirt. He didn’t look like himself any longer, making the fear inside rise as Kaeya felt his stomach drop.
They’d been stupid. Too stupid to figure out what had been happening that week.
“Best out of three , remember?”
It wasn’t flirtatious, and it wasn’t for fun anymore, Diluc’s foot was pressing into him a little too firmly for comfort, and Kaeya tried to push him off, his fingers trembling as he did his best to stay focused- to stay conscious- because no matter what, he couldn’t have his first heat in front of the Alpha.
“Diluc- I need to go- It will be bad if I stay.”
His stomach was twisting up in knots, and Kaeya could barely handle being under the Alpha, excitement filling up every inch of him.
“But you’re liking this.”
The comment was accompanied by a cool smile, Diluc shifting his foot off Kaeya and dragging his sword down, ripping the flimsy fabric of his shirt all the way to his trousers.
It was terrifying, but welcome, the cool breeze providing Kaeya some comfort as he took deep breaths, trying to stay calm. He made an attempt to leave, scrambling as quickly as he could, to no avail. Diluc easily grabbed his legs. He’d always been just a little bit stronger, having trained for a claymore, and his fingers went to his trousers, tearing them at the seam, hungrily reaching for Kaeya’s ass as if he were a piece of meat.
“You smell so good- I always hoped- I knew you’d be my omega-”
Diluc could have cared less about what Kaeya wanted, too pent up to care that what he was doing was going to get them both into trouble. For all his years of being good- it seemed that the first opportunity at being placed in front of an omega in heat was Diluc’s undoing.
“No- No Diluc- Stop-” Kaeya felt his fingers against his ass, wincing as he felt the slick dripping out, disgusted with how good it felt. He didn’t want Diluc to take him out in public- where anyone could see- and not when they’d never even kissed .
“I know what you need- You’re an omega- I’m going to make you feel good. I’ll take care of you.”
Diluc was insistent, forcing his fingers into Kaeya’s ass, making him give a moan as he covered his face, shamefully enjoying his friend’s touch.
“I don’t want this- Diluc- Please”
Kaeya was fighting with himself, torn between his desire to chase the pleasure he was feeling, and filled with fear at the Alpha’s rut. Diluc would have never considered doing anything like that to him unwillingly, but he wasn’t himself, and his scent was making Kaeya dizzy, making him hard and needy, sprawled in the dirt for Diluc.
“You do. You’re squeezing down already..”
He gave a needy whine as Diluc pushed another finger inside, and another, keeping his eyes firmly shut as he tried not to look at his expression, cold and calculating.
Kaeya put his arms over his face, hiding his expression as he felt the Alpha pull his fingers out- for a second- just long enough to push himself into the omega again, this time forcing his whole length inside. It wasn’t unwelcome anymore for Kaeya, making him melt into the ground, staying still as the Apha used him on the floor as hard as he wanted. It filled Kaeya up with pleasure, squeezing around the Alpha as his toes curled in his shoes, hands balled up tight. His teeth had cut into his own lips, trying to bite back any desire to ask for more- to beg the Alpha to knot him, or worse, to cry,
Whether it was fear, or something else, Kaeya kept his voice down, not wanting anyone to find them like that, wrapped up in each other, where he’d surely be blamed for seducing Diluc. It would be a scandal- and if anyone found out that Diluc had taken an omega during a rut- he couldn’t imagine the sort of gossip that would spread through Mondstat.
With Diluc bent over him, he didn’t even register the Alpha pushing his hands up above his head, pinning his hands to the ground as he moved harder, finally forcing a few soft moans out of Kaeya. His ass clenched tight around Diluc, embarrassed to cum while being watched, the Alpha giving a satisfied groan as he filled Kaeya up with his own knot, stretching him past what he’d ever thought possible. He gave a muffled cry, his whole body twitching as he struggled against Diluc’s hands again, being pinned down made it impossible to move away from the knot, and it only forced the Alpha closer, laying down on top of Kaeya to keep him in place.
At least the heat had become bearable again, but Kaeya knew there were still at least another two days of it, and Diluc had ruined him, making him want the Alpha again and again, his heart racing just thinking of the Alpha continuing to use him for the rest of his heat.
“You’re mine Kaeya..”
Diluc’s lips were against his ear, making Kaeya give a little shiver.
In a second he found out just what Diluc meant by his words, the Alpha’s bite at his neck finally eliciting a loud cry from Kaeya, struggling again against the Alpha.
He had to have been loud, with how the tears felt dripping down his cheeks, the searing pain coming from the bite barely dulled by pleasure. The smell of blood was sharp in the air, with Diluc looking down at him duly, finally letting go of his hands, the red smeared across his lips matching his hair.
It was too late for either of them by the time they were found, with Diluc forced off Kaeya in the evening after hours being together.
Even alone, after his wounds had been tended to, Kaeya only felt relief that they’d be trapped together forever, the bond that Diluc had unwillingly formed cementing their relationship for life.