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Empty Spaces

Chapter Text

After dark at the Angel’s Share… Lumine closes her eyes and listens to the bustle of activity in the tavern, conversations that meld together into a mass, the strumming of lyre strings, the quiet clinking of glasses and silverware. The evening invigorates it into something different than its muted presence during the day. It’s comforting, reminds her that this world is full of people, each with their own warmth in their hearts and their own burdens to carry. It brings her back when she starts to feel too detached.


When she opens her eyes again, it’s to Diluc standing behind the counter in front of her. He’s busying his hands wiping down glasses with a soft cloth. When she smiles at him, his brow creases slightly in confusion, not unkindly.


If she thinks of this world as a mystery to be solved, her own burdens feel a little lighter.


“Maybe I should join you on your little escapade,” Kaeya says from the stool beside her, leaning on one elbow in her direction. He’s swirling a wine glass in his hand; she doesn’t remember how many he’s had since they started talking. “Traveling the countries of Teyvat sounds way more exciting than being a knight. Romantic, really.”


Diluc turns his attention to Kaeya, distinctly unimpressed. “Romantic? Don’t kid yourself. She has far better things to do than babysit you. Don’t cause her more unnecessary problems than you have already.”


Kaeya laughs, the same artificial one that doesn’t quite reach his eye. “… Worried you’d miss me? I don’t recall you being so worried about my feelings when you ran off for three years.”


“I think you’ve had one too many,” Diluc reprimands without missing a beat, his gaze cold and unflappable. “You’re tapped out for the night. Sober up and go home.”


Lumine glances between them. Diluc is wiping the same glass that’s been in his hand for the past few minutes, its already shining surface catching the light above his head and reflecting the red of his hair. Kaeya stares forlornly into his near-empty wine glass as if Diluc might feel pity and retract his sentence. There’s a background tension that always seems to be present when the two of them are in the same room.


A memory catches Lumine’s mind: “And if I did have one too many, what then? You’d throw me out along with the trash?”


“—The same way you threw out father’s legacy?”


“I see no reason to cling to things that have outlived their purpose.”


“Hey, Paimon,” Lumine turns to her companion, “I think we should get going, anyway.”


Paimon gives her an affronted look, a small glass of grape juice sloshing around in her hands as she floats carelessly above the countertop. “Whaaat? But Paimon isn’t finished eating, yet! I wanted to try more of the menu!”


Lumine laughs indulgently, taking the glass from Paimon’s hands. Paimon pouts but allows it, doing a little tumble midair as she obediently makes her way toward the door. Lumine places the glass on the counter and slides it gently in Diluc’s direction.


“Thanks for dinner, Diluc. Have a nice night, Kaeya.”


Diluc nods and Kaeya smiles. Lumine stands from her seat and follows Paimon toward the exit, holding out her hand as Paimon flips and flits like an energetic crystalfly on their way out.




“I really don’t get it,” Paimon muses as they meander through Mondstadt, the night sky bright with stars above them. “Why don’t those two get along? And why do they still hang around each other if they hate each other so much?”


Lumine hums thoughtfully, her eyes on the horizon. When she’d been able to traverse the universe with her brother, individual worlds had felt so small. Now, with that power stripped from her, this world feels massive, like a universe in itself.


“Traveling this world,” she begins, turning to Paimon as they walk, “I’ve met so many different people, done so many different things… I’ve never really felt lonely. But I think that’s only thanks to you.”


Paimon looks surprised, her eyes becoming wide and round. She appears to become flustered for a moment, fidgeting bashfully in what Lumine recognizes to be a mixture of happiness and pride.




“If I hadn’t met you and didn’t have you here guiding me now,” Lumine continues, stopping in place and looking skyward, “this world would have only felt… empty. I would have looked at the horizon and been consumed only by thoughts of how far my brother was beyond it. I would have stayed a stranger in this world.”


Lumine allows herself a moment to imagine it. She thinks of herself walking this world alone, an alien world devoid of familiarity, no people or connections to call her own. The land surrounding her becomes cold, dark, and empty. It stretches on for an unimaginable distance, leaving her feeling incredibly small and lost. The one place—the one person— familiar to her is somewhere she can’t go, a star buried in that horizon. She’s powerless; pushing the air from her lungs, it’s like drowning.


But Paimon appears in her line of sight and the vision dispels.


What would happen, if…?


“I think I’m beginning to understand the people of this world a little. It almost feels like home.”


It feels like there’s something looming over her back. At the end of it all, what decisions are awaiting her? What would she gain? What would she lose? I’ll miss it here when I move on, are the words she doesn’t say.

Chapter Text

The Pyro Vision sparkles like a red gem when Kaeya holds it up to the light. It doesn’t glow or let off any heat, not anymore—not since Diluc had abandoned it. How it’d come to be in Kaeya’s possession, well… Jean had given it to him, actually. She’d probably thought it the right thing to do. She couldn’t have known better.


He really shouldn’t have accepted it. He’s moved all his belongings out of the Ragnvindr manor. Crepus is dead. Diluc is gone. It’s just himself and… what? This rock? A memento of his second life?


But he can’t bring himself to put it away. It remains face-up on his desk and stares at him every time he comes back. Self-loathing bubbles up inside of him at the sight of it, a Pyro Vision gone as cold as his own—once glimmering with pride, once loved by someone. Was the world always this empty? It’s not the first time he’s seen his life in ruins, and this bauble is like a looking glass back into those days.


“Don’t look at me like that,” he says, hands falling heavily on the desktop, hair spilling over his shoulders. “I didn’t want this, either.”


He tells himself it’s the last truth he’ll allow in this new life.








It’s almost closing time. Kaeya never left; he’s sitting in the same spot with his head in the palm of his hand, dozing away. Diluc admits to himself that it isn’t that typical for this to happen, meaning he’s had more to drink than usual. The remaining patrons are even giving him a decent amount of girth, leaving the bar essentially empty save for Kaeya and himself. It’s thoughtful of them but leaves Diluc in a difficult position. He should have been more forceful about kicking Kaeya out earlier.


“I don’t recall you being so worried about my feelings when you ran off for three years.”


Diluc is scrubbing a hole into the glass in his hand. Kaeya’s presence always seems to complicate matters, despite Diluc’s pointed efforts to bury their past. He once thought he’d made the status of their relationship crystal clear, but following his return to Mondstadt, they’ve somehow fallen back into semi-regular contact with each other. It’s mostly Kaeya’s fault, so he likes to believe, but maybe he’s been too soft. Kaeya’s been more loose-lipped than usual under the influence of alcohol, grains of truth slipping through cracks in his carefully constructed front. It’s dragging Diluc back to a very dark moment he isn’t keen to revisit.


The real truth is that Diluc doesn’t recognize the person sitting in front of him, not really. Maybe that’s natural after being away for years, but it’s more unnerving than he’d like to admit. Kaeya had already reinvented himself by the time of Diluc’s return, a stark reminder of what felt like a lifetime of deception. He talks differently, dresses differently, lies differently. Or perhaps it’s more accurate to say that he’s less restrained, without the stifling restrictions of the Ragnvindr household or the claimed obligations to some distant, lost country. A clean break, he says. But he lies even more than before, and a part of Diluc recognizes that it may be his fault. When he even lets himself consider it, which isn’t often, an inkling of guilt drops into the pit of his stomach. He considers the possibility that the two of them have suffered a tragic misunderstanding.


Kaeya had been more than just dear to him. That’s why he can’t forgive and forget so easily, especially when the distance between them is this vast. Kaeya is a stranger there sitting at the bar, but he’s also achingly familiar, snoozing without a care, blue hair cascading over his fingertips. The chasm that they’ve eked out together is painful like this. Diluc is holding on to his grudge with an iron grip.


When the last customer leaves the tavern and it’s time to close, Diluc pours water into one of the glasses he’s overshined and places it on the counter in front of Kaeya.


“Wake up.”


Kaeya doesn’t quite startle awake, but he does come to quickly, to his credit. He’s a light sleeper, this Diluc knows, and not quite careless enough to really knock out in the middle of a tavern.


“It’s that time already?” he asks, still looking drowsy.


Death After Noon isn’t a joke, even if Kaeya throws it back with a certain level of expertise. He stretches out like a lazy cat, his ridiculous-looking jacket riding up and bunching in awkward places. Diluc finds himself inexplicably annoyed. He stifles the urge to overturn the glass of water on Kaeya’s head.


For his part, Kaeya seems to have just noticed the water exists. He pulls it close to himself but doesn’t drink it.


Diluc begins again. “So? Why are you still here? I recall telling you to go home hours ago.”


“You seem to think I have some ulterior motive,” Kaeya laughs. “I just didn’t get that much sleep last night. The Acting Grand Master works me to the bone, you know.”




“If by you, you mean your lackeys.” Diluc honestly almost feels bad referring to Amber that way. “Don’t bring Jean into it. I’m sure you can come up with better excuses. It’s what you’re good at.”


Kaeya’s brow tilts at that, but they’re interrupted before he can respond. One of Diluc’s informants bursts through the doorway, an urgent “Master Diluc!” shooting through the empty space. No sense of subtlety at all, really. She does notice Kaeya almost immediately, no doubt expecting the tavern to be empty after hours. Kaeya smiles innocently as her gaze drifts uncertainly between the two of them. Diluc normally makes it very clear not to bring their business to the attention of the Knights of Favonius. Even if they’ve both danced around saying it aloud, he knows Kaeya is aware of his identity.


“It’s alright. Go ahead.”


Kaeya leans back against the countertop and feigns disinterest.


“… It’s just,” she starts again, with some hesitation, “we’ve been tracking the movements of another Abyss Mage lurking around the city. Honestly, we have some suspicions it might have been drawn here by the Honorary Knight. Lately…” her tone becomes thoughtful, “I think some of the Order has taken an interest in watching her? We might have a pinpoint on its location for interrogating.”


That won’t do. Not that Diluc wouldn’t dispose of the pest anyway, but he does owe Lumine a favor. He accepts the parchment the informant holds out to him, some ruins close to Mondstadt marked on a map, along with a trail of the mage’s usual patrol patterns. There are other notes scribbled in the margins, some observations and some questions to be answered.


“Thanks. I’ll take care of the rest.”


The woman nods politely and leaves the same way she came. Diluc wordlessly retrieves his coat from a hanger in the back, pulling it on and slipping the parchment into one of its pockets. On his way out and somewhere between pulling on his gloves, he kicks at one of the legs of the stool Kaeya is sitting on, hard enough to force him to stumble to his feet. Kaeya is at least gracious enough to take the cue, following Diluc out the door with the same serene, mildly amused expression on his face.


“Not even going to invite your guest along? That’s rude,” he says.


“You’re not invited,” Diluc confirms, closing the door behind them and turning the key. “Nor are you my guest.”


“You have no problem accepting help from a certain Honorary Knight, as I recall,” Kaeya retaliates, something about the way he says it making Diluc turn, “and I’ve got nothing better to do.”


It turns out that chasing Kaeya off is more trouble than it’s worth. Diluc isn’t sure exactly how it happens, but he’s off into the wilderness of Mondstadt with Kaeya at his back. They haven’t done anything like this in quite some time, not since Diluc’s knight days. They’re both older and different now. Kaeya looks right at home under the moonlight.


The ruin entrance is a bit inconspicuous, just a hole in the side of a cliff. There are clear signs that it’s been in use, though, the interior all aglow with blue light. Diluc can sense the traces of elemental energy. Kaeya steps ahead of him, following the same footprints.


“Actually,” Kaeya says just before vaulting himself over a small incline, “I’d be lying if I said I didn’t have my own interest in what you’re doing here.”


Diluc shoots him a questioning look, but accepts the hand he offers, Kaeya pulling him up smoothly. “What are you talking about?”


“I mean, you don’t think there’s something a little strange about that traveler? Don’t get me wrong, I do like her… but you must have noticed that she doesn’t use a Vision.”


“I’ve noticed.”


Diluc glances around the chamber they’ve come into. A group of hillichurls are stirring to life in the far corner, which is about as expected. Not so expected is the lawachurl amongst them—They aren’t that common in Mondstadt, except near the Liyue border. Diluc materializes his claymore as the titan beats its fists together, approaching him not by walking but with a giant leap. He barely dodges that and the rocks that go flying when it splits the floor apart.


Kaeya, being much nimbler on his feet, has already shot off to deal with the smaller ones. Diluc decides to leave him to it and instead keep the big one occupied, bringing his weapon to life with flames. The fire gives his blade some extra dig into the lawachurl’s thick armor, but this isn’t normally a one-man job. In all honesty, Diluc hadn’t expected the security to be this tight. The lawachurl grabs his claymore on the next strike, so he dissolves the blade and jumps back.


It's something he just catches out of the corner of his eye, a flash of gold slipping down one of the corridors out the chamber. Kaeya spots it, too. He takes off after it almost immediately.


“Kaeya, wait!”


A wall of ice shoots up between Diluc and the lawachurl, though a portion of it smashes under the beast’s giant fists. Diluc doesn’t really think twice about it; he turns and runs after Kaeya. By the time he makes it to the corridor, however, he’s already lost sight of Kaeya and whatever thing he’s chasing. The vague sense of alarm he feels (and the lawachurl still pursuing him) keeps him moving, haphazardly dodging traps and vaulting over obstacles until he thankfully comes to a ravine he needs to cross by gliding. The lawachurl, being both heavy and clumsy, is unable to come to a stop in time. It careens gracelessly over the edge, leaving Diluc in peace for the moment.


There’s another chamber where he lands. It has some elaborate pattern on the floor, like a snowflake, and Kaeya is standing right in the middle of it. It’s quiet; there’s nothing else there.


Without much warning, a Cryo Abyss Mage pops into view right in front of Kaeya, its shield almost touching his face. Oddly enough, it doesn’t do anything right away. It just stares into Kaeya’s eye for an unsettling amount of time, as if in a trance, until Kaeya seems to get over his surprise long enough to swipe at it.


“Intruders! Intruders!” it cries in a high-pitched voice, blipping in and out of sight. “Oh, this won’t do… The Prince is…”




The pattern on the floor comes to life, suddenly. Diluc realizes too late that the Abyss Mage is using it to amplify its power. The ice spike that shoots out of the ground catches Kaeya in the side, coloring the tip of it in a glistening red. He stumbles, gripping the fresh wound.


Diluc starts forward, but a Pyro Mage pops into his path, bursting with flame.


“Oh my,” it cries fretfully, “Who let them in? What incompetence!”


“Incompetence!” A Hydro Mage joins the call. “Where are the guards? Unacceptable! This reflects poorly on us!”


Two Ruin Guards appear as if summoned, both heading in Diluc’s direction. Kaeya tries to join him, but nearly gets impaled on another ice spike. He’s trapped as long as he’s standing on that symbol, Diluc realizes.


This is… very bad.


“Aaaaaah!” the Pyro Mage continues its tirade, spinning around and pointing directly at the Cryo Mage from inside its bubble. “This is YOUR fault! You were supposed to be the first line of defense! Why didn’t you stop them at the gate?!”


“Well…” The Cryo Mage responds meekly, looking down at Kaeya, “That was…”


“Just hit the self-destruct, you clown! You buffoon!” it rages. “Unless you’d like to answer to the Prince personally!”


“Noooo! No, no!”


“Now, now…” Kaeya calls out in a pained voice, holding out his free hand. “Surely we can discuss this?”


“Shut up!” the Pyro Mage hisses.


The Cryo Mage holds up its small arms. The symbol starts to glow again, this time blindingly bright. Diluc has a sinking feeling in his stomach. He tries again to get to Kaeya, but the two Ruin Guards slap their arms against the ground, forcing him back further.


“I’m sorry, so, so sorry!” the Cryo Mage frets. “Oh, Prince!”


The ground beneath them starts to split from the center of that symbol. There’s enough time for Diluc to escape if he turns back, but he hesitates; Kaeya is still stuck at the center, spikes shooting up at all points to block him in. When their eyes meet briefly, a pull like gravity, Diluc knows that he isn’t going to move. His feet feel soldered in place.


There’s a sense of weightlessness when the floor beneath them first starts to give. Then, everything crumbles. Diluc sees a memory flash before his eyes.


“Oh, you know,” Kaeya laughs, his face younger. “I’m fine with you taking all the glory, Diluc. You’re the true heir of this house. And I can get away with a lot more when all the attention is on you…”


Ah… so, that’s why it seems so strange.




When Diluc comes to, he isn’t sure where he is. His body is half-trapped under rocks. There’s water everywhere.


He tries to muster the energy to free himself, the fog in his head making it hard to focus. He has an image in his mind—It’s that Abyss Mage and Kaeya in the center of that chamber, staring each other down. Diluc has no claims on someone he’s cut out of his life, but selfishly he realizes that he expects that Kaeya won’t just slip away to some unknown. Kaeya had expressed his loyalty to Mondstadt and to Diluc, and Diluc… well.


It's a right mess he’s gotten himself into. He shoves at the rocks covering him, slowly unearthing himself from the rubble. His entire body hurts, but he thinks he can move. Broken ribs, at the very least. Very slowly, he pulls himself up.


Kaeya. Where is he?


Diluc wades through knee-high water until he finds him. The ice is a breadcrumb trail, splayed along the rocks like spiderwebs. Kaeya must have already regained consciousness at some point; he’s sitting atop a patch of ice rather than underwater. He doesn’t look to be awake anymore, but it’s heartening to see some sign of life.


Wading over to the edge of the ice, Diluc clumsily crawls on top of it, trying not to slip. He has to move on his hands and knees over to where Kaeya is sitting. There’s blood crusted on Kaeya’s face, originating from his hairline. Diluc settles himself down carefully, reaching out to cup Kaeya’s face in one hand and push his hair back with the other, checking the severity of the injuries. He lets out a breath he’s holding when he doesn’t find anything that looks too serious; the biggest problem is the wound on his side and any potential internal bleeding. Kaeya is still holding the wound, his outfit stained dark red with blood.


“It’s not as bad as it looks,” Kaeya surprises him, looking up at Diluc the best he can from his position. He’s paler. “But it’s sweet of you to worry.”


Somehow Diluc doubts that. Nevertheless, a knot of panic in his chest seems to relax slightly at seeing Kaeya awake.


“Tell it to the Deaconess,” Diluc grumbles, gentler than usual.


He starts to pull Kaeya around him without waiting for prompting. The faster they get out of this place, the better, even if it feels like they’ve accomplished basically nothing. Kaeya struggles with standing but he follows Diluc’s lead the best he can.


“No point in both of us dying, you know,” Kaeya says once they’ve set a consistent pace. “Why didn’t you try to escape?”


“… I couldn’t.” Diluc doesn’t like how the question makes him feel. The next words he wants to say try to stick in his mouth like glue. “Not when it’s you.”


Once upon a time, Diluc would have died for him. It seems that’s still true, to his own surprise. The two of them had once been inseparable; they’re still together now, in a fragmented parody of the past. Their differences seem utterly meaningless when Diluc realizes that it’s only their own hurt keeping them apart. But then, what was the meaning of that moment? Diluc had just lost his father, and Kaeya had chosen that moment to say to him, you never really knew me. The world before him, everything that had become familiar to him until then, had completely cracked apart like a fragile sheet of glass. Like losing not one, but two of the most important people in his life. The only two people.


Diluc occasionally wonders if Kaeya had ever felt any grief at all over their father’s death. But, looking back, it’s that moment that had acted as the trigger to all of this. There’s probably another truth buried there.


Kaeya laughs softly, something that sounds honest but sad, placing his hand on Diluc’s chest. “Hey, it’s okay.”


Diluc wonders what sort of expression must have been on his face to elicit that response.

Chapter Text

Diluc doesn’t come often to the Knights’ Headquarters, never at all to the wing that hosts their personal quarters. It’s been a couple of days since he and Kaeya had last seen each other. His body is still sore and covered with bruises. Barbara had done her best with both of them, of course, and thankfully hadn’t asked too many questions. It takes him some time to finally find the door to Kaeya’s residence. He actually hesitates for a moment before knocking.


“Come in!” it’s a child’s voice that answers, which does absolutely nothing to alleviate his hesitation.


He’s no coward, though, so he does open the door. He doesn’t really know what to make of the sight that greets him there. Kaeya is sitting on the floor in front of a cocktail table, Klee propped up on his lap. Paper and crayons are scattered all over the table’s surface, an aquamarine color held in Klee’s hand. She looks up when he enters but seems disappointed by what she sees. Diluc isn’t sure how to feel about that, either.


“Oh, wow!” Kaeya exclaims, drawing Diluc’s attention away from the child. “What an honor! The young master Diluc himself has come to check up on me.”


“Poor Kaeya,” Klee croons, scribbling something else on the paper in front of her. “I’ll make him feel all better.”


For the first time, Diluc notices that there’s a bright pink bandage over one of the bruises on Kaeya’s face. The entire scene is very… domestic.


“Uh, huh…” He’s at a loss, really.


Kaeya seems to take the hint. “Hey, Klee. Master Diluc and I have some adult stuff to discuss. We’ll play more later, yes?”


“Adult stuff?” Klee seems confused. “Well, alright. If you say so.”


Klee neatly places all her crayons back into the designated box, gathers up the scattered papers, and makes her way out with her arms full of her various art supplies. Diluc gets the door for her.


When he’s sure she’s gone, he moves over to where Kaeya is still sitting, dropping down next to him and resting his back against the sofa behind them. Kaeya is watching him the whole time with a look of slight trepidation. It’s annoying, so Diluc reaches over and grabs the bandage on Kaeya’s face, ripping it off in one smooth movement.


“Ow!” Kaeya grabs his face, affronted.


Diluc rolls up the bandage between his fingers and flicks it away. “I never got the chance to ask you… Did you see anything when you ran ahead back there?”


“All business, huh?” Kaeya looks away noncommittally. “… I didn’t see anything. Must have been too slow.”


It’s not that convincing. Kaeya is anything but slow, considering how long his legs are, and he has the most stamina between the two of them. Just this time, Diluc lets it go.


“No, I’m not here for business,” he says instead.


That draws Kaeya’s attention back to him. “… Pleasure, then?”


Once in a while, it would be nice if Kaeya would just keep his mouth shut. Diluc takes Kaeya’s hand to pull it away from his face, giving himself space to lean in and press their lips together. Kaeya opens up for him without any resistance whatsoever; his arm comes around Diluc’s shoulders, grabbing the fabric at Diluc’s back. They’ve done this a thousand times before. It kind of hurts how easy it is to fall back in again.


“You smell different,” he mutters when they finally break apart, moving to press his face into Kaeya’s neck.


Kaeya laughs humorlessly, probably at the absurdity of it all. Honestly, he’s more beautiful than Diluc remembers.


In the end, Diluc isn’t sure what any of this means. The way Kaeya says his name into his shoulder is with an aching, pained yearning that so closely resembles his own it makes him shake. For years he’d ignored it, refused warmth from anyone. When had that started to change?


I love him, he thinks, the ferocity of that feeling enough to strangle him.








“I used to believe... if I was to stamp out evil, I would have to walk alone in darkness. However, seeing your perseverance, I know I was wrong. Friend... I owe you my thanks.”


Lumine sits alone on a hill, hands in her lap, staring up at the sky. Somewhere, on the other side of that horizon, her brother waits for her.


It’s closer than she thinks. Not so far away, Aether steps out under the same windy, Mondstadt sky.


“Oh, Prince…” the Cryo Mage warbles at his feet, rubbing its face with tiny hands. “I saw the stars in his eye…


“Another lovely Prince...”