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It’s been four months since Kaeya discovered Diluc’s Abyssal Power and though his brother hasn’t yet become a threat, Kaeya can feel it in the air that something is coming.
Something is going to happen, something soon, and it’s going to involve Diluc in more ways than one.
It’s early morning and Kaeya is once again very reluctantly dragging himself out of bed. Varka has been running them all ragged, worse than he ever was before, and there are days when Kaeya thinks if he sees the Grandmaster, he’ll wring his neck.
He drags his feet to get ready, only half awake as he goes through the motions of breakfast, coffee, and getting dressed.
When he shuffles in front of the bathroom mirror to brush his hair, Kaeya looks at his reflection and catches sight of his right eye—uncovered by the eyepatch that he prefers not to sleep with.
Sucking in a breath at the sight of it, Kaeya looks down as his mind drifts to Diluc, as it usually does lately.
Diluc looked different. Still bloody, but now he wore Childe’s Delusion, harnessing the power of two Fatui weapons as he battled Dottore at the end of the hall. But there was something off about him, each move towards the doctor sloppier and less coordinated than the last.
And then Kaeya saw Diluc stumble and change and he could only stare with wide eyes as that same monster Chlde had turned into now took his brother’s place.
Kaeya paused, frowning as something tugged at his mind, urging him to look closer, to notice what was staring him in the face, to see what he was missing.
What was he missing?
“What the fuck!?”
“That’s not possible,” Childe rasped from where he lay in a pool of blood a few feet away. Kaeya struggled to his feet, limping over to him only to collapse across the floor from him.
“That’s the same thing you had,” Kaeya muttered. “What the fuck is that thing?”
“In two words?” Childe rasped. “The Abyss.”
“What!?”
“It’s my Foul Legacy but it’s because of my connection to the Abyss.”
“You have what?”
“But that shouldn’t be possible for Diluc. He shouldn't be able to access that, let alone–”
He was cut off by a shout and both Kaeya and Childe turned to watch, numb, as the large hand of the Foul Legacy wrapped around Dottore’s neck and twisted.
Kaeya squeezed his eyes shut. “What am I missing?” He whispered. “What am I missing !?”
“You came from the Abyss then.” Kaeya went tense and Childe shifted. “That’s it then. You’re from the Abyss. You’re Khaenri’ahn. But that’s not why Master Duluc hates you. No nation teaches their children about Khaenri’ah. Which means you must have had some sort of secret–”
“Enough!”
“I’ve struck a nerve. Which means I’m right.”
“No, it means you’re annoying.”
“For what it’s worth, I’ve got no problem with it.”
“With what?”
“You being Khaenri’ahn.”
“I don’t give a shit about what you think.”
“Why does that matter?” Kaeya asked. “What does that have to do with Diluc, why does that matter?”
“Shit, Luc.” He squeezed him tightly and Diluc let out a breath, struggling to find the strength to wrap his own arms around Kaeya. “I was so worried you were dead.”
“I’m not,” Diluc mumbled. “I don’t think I am, anyway.”
“No, you’re not. Come on, we have to get out of here.”
“Kaeya, wait. Something’s…wrong…Dottore did something to me. He…put something in me. Kae–”
Kaeya’s eyes snapped open. “ Shit ,” he hissed. “Dottore gave Diluc his Abyssal connection.”
Taking just enough time to secure his eyepatch, Kaeya turned and sprinted out of his apartment.
……………………………
Diluc was tired. He hadn’t been sleeping well and though he had gained a decent amount of control over the Khaenri’ahn star, it almost felt like training nightly with Dainsleif was more draining than using his Vision.
Though he’ll never say it outloud, he’s glad Dainsleif had finally decided he was strong enough to no longer need constant training. The man had made him uneasy and uncomfortable and so knowing Dainsleif is no longer in Mondstadt takes a great weight off of Diluc’s chest, even if he feels a little bit guilty.
Dragging his hands through his hair and carelessly pulling it back into a tail, Diluc trudged over to the vanity in the corner. Without much thought on his own, he found his mind drifting back to the chaos that had consumed his life several months earlier
The moment Diluc saw the cause of the commotion, it was like everything in him just shut down.
All he saw was this giant, hulking beast standing over his brother. And then the next moment, Kaeya was flying through the air as a strike from the monster sent him across the clearing.
Diluc didn’t give the knights or even the creature itself a second thought as he took off towards his brother who had hit the ground with a sickening amount of force.
“Kaeya!” Klee screamed as she raced after him. Somewhere under his worry for Kaeya, Diluc knew he probably should have made her stay behind, especially when they didn’t know what the creature was, but right now his biggest concern was the fact that his brother wasn’t moving.
Diluc closed his eyes, drawing in a slow breath. “I’m sorry,” he whispered.
As they fought, Diluc’s anger grew and something in his chest went colder and colder but he struggled to ignore it and keep fighting—struggled to hold his ground and end this.
And then Dottore opened his mouth.
“I was the one who did it, you know. Summoned Ursa the Drake to Mondstadt, I mean.”
The cold got colder.
“I was the one who made sure that Delusion would end up on your father’s hand.”
His chest went tight.
“And I was the one who ordered the death of Crepus Ragnvindr.”
The cold snapped.
Diluc rested his elbows on the top of his vanity, burying his head in his hands as he tried to think about anything other than the events of Snezhnaya.
“Now that you’re making noise, we can finally get started. Ah, but first. Consider this a gift.”
Dottore slammed his palm into Diluc’s chest and ice engulfed his body as Diluc screamed until he passed out.
So much had happened, too much had happened, and all of it was on account of that damned star.
As the mitachurl brought its blade down, the tension in Diluc’s chest finally snapped and a sensation the likes of which he could never explain took over his body, the star appealing as power he didn’t even know he had shot outward, killing and destroying every threat in the room in an instant.
As soon as the monsters were gone, Diluc’s body grew heavy and he stumbled. Struggling to lift his head, he made eye contact with Kaeya who stared at him in horror before his own eyes fluttered shut and he fell to the ground, unconscious.
How many more times was Khaenri’ah going to destroy his and Kaeya’s relationship?
“Kaeya, I don’t know what you're talking about.”
“The star, Diluc!” Kaeya shouted, finally losing his composure as he jerked to his feet. “The Khaenri’ahn star you summoned in the Domain to eradicate the enemy! The Abyssal power you used to save my life!” Diluc gasped when Kaeya reached down and grabbed him by the front of his shirt, forcing him upright until his arms strained, the cuffs biting into the flesh of his wrists. “Do you think it’s funny to call upon the very same place I see in my nightmares!? Do you think the Abyss is a game!?”
Diluc stared up at him, eyes wide as terror raced through his body. He didn’t think he’d ever been more sure that Kaeya would kill him than he was now.
How many more times were going to be Diluc’s fault?
“Diluc…I’m from Khaenri’ah.”
Diluc didn’t hear him. Surely he hadn’t heard his brother right, surely the storm was too loud. But no, Kaeya was looking up at him with sorrow in his eyes and Diluc knew, without a doubt, that he had heard his brother loud and clear.
Their fight was too fast and too long, the wet of the rain and heat from his Vision blinding Diluc to his actions and the true consequences they would bear. He was only snapped out of his rage by the ice of Kaeya’s brand new Vision freezing the flames on his blade and sending him flying back from his brother.
Neither of them moved then, for a very lng time, as they stared at the Vision hovering above Kaeya. When his brother accepted it and the true reality of what he had just tried to do sunk down on the Ragnvindr heir, Diluc slowly stood and stalked over to Kaeya who frantically got to his feet, fear in his eye.
“I want you out,” Diluc said. “Out of the house, out of the family, out of my life .”
Kaeya trembled before him. “Diluc–”
“I hate you!”
How much longer was it going to take until there was no more relationship left for Diluc to destroy?
“Kaeya, you’re hurting me–” he says weakly, but his words barely seem to faze his brother.
“And you didn’t hurt me!?” Kaeya threw him down and stared down at him.
DIluc cowered beneath him, terrified. “Kaeya–”
The next words out of Kaeya’s mouth have Diluc’s heart stopping, blood freezing in his voice.
“I hate you,” Kaeya declared, voice deathly calm as he turned and stormed out of the room.
Diluc sighed and stood, walking over to where his coat hung over the endboard of his bed. Reaching for it, he never got the chance to put it on before his bedroom door flung open and he spun around to find Kaeya standing there.
All he managed to get out was “Kaeya, what–” before his brother rushed over and grabbed him firmly by the shoulders, shaking him in an almost frantic manner.
“Show me the star!”
“W-what?”
“Diluc, show me the Abyssal star!”
“Kaeya–”
“ Now !”
Diluc summoned it without hesitation but he regretted that choice when the moment it formed above his palm, Kaeya grabbed it and flung it across the room.
Pain exploded through Diluc’s body and he could only vaguely hear himself screaming as he fell into Kaeya’s arms, unable to control himself and unaware of anything beyond the agony in his chest.
Maybe he was speaking through the screams, maybe he was pleading .
All he knew was that when he lost consciousness this time, it was more than willing.
……………….
Kaeya stared down at his brother as he went limp, not having expected such a reaction. Thundering footsteps sounded in the halls and Kaeya felt numb as Adelinde stumbled into the doorway.
“Master Kaeya–”
“It’s okay, Adelinde.” Kaeya hardly recognized his own voice as he slowly set Diluc on the ground before moving over to where the star lay. “He’s fine.”
“Master Kaeya–”
“I’m going to take him back to my office with me,” Kaeya decided, feeling almost like he was having some sort of out of body experience as he stared down at the glistening star in the palm of his hand. “We need to have a talk.”
He didn’t look at Adelinde as he tucked the star safely on his person, moving over to lift Diluc into his arms. Adelinde stepped out of his way as he left the room and he could feel her eyes on his back the whole way down the stairs.
…………………….
Diluc wakes slowly. He thinks his head hurts, though it’s hard to tell through the muggy, stuffed-cotton feel. His body is sluggish and tired and whenever he tries too hard to remember what happened last, pain spikes behind his eyes and makes him regret that movement.
He floats in some sort of half conscious half not state before the pain and fuzziness fades enough that he’s finally able to find the strength to peel his eyes open.
What greets him is the ceiling of what he’s pretty sure is Kaeya’s office in the headquarters of the Knights and after a few moments, he thinks he does finally remember that Kaeya had been there before…whatever happened.
As awareness returns to him, so too does everything else and he notes the way his chest feels uncomfortably empty and hollow; entire body simultaneously too hot yet far too cold. He’s shaking though he doesn’t think he’s shivering, but there’s no denying the way his body trembles without his own intent.
He feels like he can’t breathe, even as each breath comes in as smoothly as it does naturally. His entire body feels on edge, wired, out of place yet he cannot exactly place why .
When his limbs stop buzzing, numb, he manages to turn his head at the distant sound of a chair against wood and finds Kaeya standing from his desk and moving over to where Diluc lays on what must be the couch.
“Kae–” He begins, voice hoarse. It’s hard to speak, hurts to speak, and he thinks he somehow distantly remembers screaming.
His brother talks over him though and doesn’t let him finish his question as he stops next to the couch and orders,
“Hold out your hand.”
Diluc blinks, slow and sluggish and mind struggling to process the words and their meaning through the exhaustion blanketing him. But it has been ingrained in him since he was a child to obey orders without thought and he finds himself complying even if he hasn’t quite processed the words Kaeya has said.
Holding out his hand, Diluc watches as Kaeya places the Khaenri’ahn star into his palm. The moment it makes content, everything fades and he feels perfectly normal, eyes fluttering as he lets out a quiet sigh as the pain and exhaustion vanish in an instant.
Kaeya steps back from the couch and Diluc very slowly sits up as the star fades, returning to the part of his chest it has carved out for itself. He doesn’t dare look up at his brother, instead listening as Kaeya turns and walks away to return to his desk.
Expecting to be sent out the very moment Kaeya has gotten whatever it was he wanted, Diluc is startled to look up and see Kaeya watching him with a contemplating gaze.
When their eyes lock, his brother sits up and crosses one leg over the other, leaning back in his seat and speaking firmly.
“I think we need to talk.”
Swallowing thickly, Diluc nodded and stood as he moved to take a seat across the desk from his brother.
“Yes,” he agreed softly. “I think we do too.”