Chapter Text
The day was shaping up to be quite ordinary for Mondstadt. The city had its own rhythms, to the point that Kaeya could tell the time of day by whoever's footsteps he hear on the cobblestones. Ah, but of course, it was at times like these that it paid not to be complacent.
He'd coaxed Diluc into an early lunch that day--in truth, most of Diluc's lunches were early, because he liked being on-hand for the lunch rush at the tavern--but that was why they were both sitting at an outdoor table just before the tavern opened at noon, enjoying the warm breeze and a Sweet Madame. Diluc was drinking his insufferable grape juice, while Kaeya, in deference to the early hour, had a glass of apple cider instead of his preferred wine.
"It wouldn't do for a Knight of Favonius to be seen drinking so early in the day," Kaeya had told Diluc with an air of professionalism that was carefully constructed, if not completely feigned.
Diluc, who despised drinking as much as he did the Knights, ground his jaw tight to stop his cheek from twitching in that way it did when he was annoyed. This amused Kaeya so much, he didn't even mind foregoing the wine.
But yes, that was why they were sitting outside having lunch together that day. Kaeya had a clear view over Diluc's shoulder of the tavern entrance, and so he was the first to see the Traveler and Paimon round a corner.
They stopped by the door, obviously unsure if it was open yet (it was not) and whether, knowing the tavern was not open, they might hazard to go in anyway, but then Lumine looked over and spotted them, so the point was moot.
In truth, this too was part of Mondstadt's routine nowadays. The Traveler and Paimon were a commonplace sight, even when they popped up where you least expected them. Errands and commissions had them going to and fro all of the time, and so Kaeya was not terribly concerned to see them, though he was curious to know who had them making the rounds this time and for what purpose. Their daily activities were an impressive grab-bag of completely mundane chores and heroic feats that could go down in legend, and Kaeya found this kind of unpredictability both amusing and something he might find useful.
But thoughts of what brought them to Angel's Share turned from amused to sobering as Kaeya watched them approach. There was a tension there; ill-concealed. Portending something dire.
"Why, look who it is," Kaeya remarked loudly as the two approached. "Already at it this early in the morning?"
This was when he expected Paimon to start berating him for being a hungover drunk, and telling him off because it was late in the morning when people were already awake for hours, but Paimon was hovering in tight at Lumine's side, small hands touching her shoulder in what might have been fretfulness, but Kaeya suspected was merely a show of support. Lumine's own hands were quivering tense, worrying at the hem of her skirt and wrinkling the fabric.
"Master Diluc," Lumine said, her voice as clear and calm as ever, "have you seen Venti lately?"
Diluc turned to look at her, missed the worry in her hands and looked into the tidy lines of her face. No, it wasn't calm, Kaeya thought. It was a blankness, if anything. Kaeya knew that type of mask well.
"He doesn't spend all his time at Angel's Share, despite what rumor would have you believe," Diluc replied. "But if I see him, I can tell him you're looking for him."
"Okay, thank you, Master Diluc!" Paimon piped up, while Lumine nodded; resigned.
"Thank you," she repeated more quietly, and turned to leave.
Kaeya continued watching the subdued departure, still trying to pinpoint what about the Traveler's demeanor struck him as out of place, but she had scarcely taken two steps when she stopped in her tracks, shoulders stiff. She turned towards the tavern entrance, then back in the direction she'd been walking towards, then back towards the entrance, like a poppet getting pulled in two different directions by the whims of indecision, until finally, she stomped up to the bulletin board by the tavern's door. She ripped one of the pinned notices, rolling it up, before she finally departed. Paimon did not remark at all on this behavior.
Cold prickles ran down the back of Kaeya's neck. Maybe it was nothing, maybe it was another of her odd little errands, except he was certain if he went up to the bulletin board, the paper taken would be the missing person poster Amber had helped her pin up.
The missing person posters were something of a curious detail, stirring some amount of gossip when they first went up. In content, they were vague; a blond young man in exotic clothing? How baffling, the Mondstadtians thought at first. There were any number of young blond men running around, and what even qualified as exotic, anyway?
As the Traveler's story got passed around, the posters felt less vague. Even if they contained no picture of the missing boy, the blanks could be filled in by the imagination just by knowing Lumine: that shade of blond, that kind of exotic clothing; and the eyes? That shade of gold gone unmentioned by the description in the poster? That, they could recognize by sight.
Everyone could keep an eye out for some outlander who resembled the Traveler, now that they knew what to look for. And if visitors to the city or strangers thought the posters were odd, well, there were plenty who were glad to explain, and draft them into the quest to find the Traveler's brother.
Which was all to say that the posters had become part of Mondstadt's milieu over the months. And now, as Kaeya walked the city after the lunch he'd pretended not to rush to finish, he was noticing the gaps where the posters were supposed to be. Bare wall met him instead, sometimes only with scraps of paper where a pin or two had been left behind.
This would ordinarily be something far below his pay grade, but as Honorary Knight, Lumine occupied a strange position in the Ordo Favonius. She had no captain she answered to, no salary she drew on, no standing orders or fixed duties. She did have a room at the Ordo Favonius headquarters, but she could have just as easily have taken lodgings at the Adventurers' Guild. The Knights of Favonius simply had an excess of available rooms with so many gone from Mondstadt, and having so few ways to reward her in proportion to her service to the city, the room she was granted was one of the small ways they showed their appreciation.
Which was to say that, whatever was happening with Lumine, there technically wasn't anyone obligated to check on her. And as Captain, Kaeya did have all the authority he required to make his own calls in this matter. He could check on her at his discretion, and it would not reveal any excessive sentiment on his part, now would it?
He went through these convolutions of thought as he attended his more typical duties around Mondstadt: checking in with informants, passing on messages, collecting information and leaving behind orders. Making his usual appearances, revealing nothing. Keeping an eye out for every missing person poster, as well as the one taking them down.
It was late afternoon when he finally made his way back to the Knights' headquarters, and crossed paths with Amber.
"Who would do this?" Amber asked--though the knight she's been speaking with shrugged and slipped away as Amber's attention turned to Kaeya instead. "Kaeya, did you see? The posters are missing! What kind of person would steal missing person posters?"
Kaeya, who'd spotted Lumine scaling up a windmill just earlier in her surprisingly meticulous cleaning spree, made only a non-committal sound in his throat.
"Say, have you seen our little Traveler today?" Kaeya asked.
Amber's eyes widened. "No! We shouldn't let her know someone is going around taking down her brother's posters! She's going to be really hurt if she hears about this!"
"How curious, you think she hasn't found out about it yet?" Kaeya asked, not quite able to stop himself from tweaking Amber a bit, even with how worrying the situation was.
"You think so?" Amber muttered. "No, but maybe if I get a new batch printed quickly enough, she won't kn--eep!"
Kaeya was slightly less conspicuous as he turned to look in the direction of Amber's gaze. At the other end of the bare, echoing corridor, Lumine and Paimon were standing, looking right at them. To close to not have heard every word as it bounced off the walls in Amber's high pitch.
Amber shouldered past Kaeya, always quicker to act than to think twice, but in this case, perhaps her blunt, earnest care was what Lumine needed. Kaeya kept back, and kept quiet.
"Lumine, are you okay?" Amber said, and caught Lumine by an arm like she was ready to pull her into a hug.
But then Amber's gaze fell to the papers in Lumine's hands, and there was a long pause.
Lumine did not react in the sticky tension of that pause, her face still blank, and Paimon, who was floating besides her, gave only a quick glance between Lumine and Amber, before looking to Kaeya helplessly.
"Um, yeah, we're both fine," Paimon answered when the pause extended just a beat too long.
"Did you... take these down yourself?" Amber asked slowly.
Lumine nodded; just a single incline of the head.
"Wh... so... you didn't... give up, did you?" Amber rallied, "I promised to help you find him, and I know we will!"
"I found him," Lumine replied.
"Oh..." Amber swallowed nervously. "Did something... happen to him?"
"He's fine," Lumine said. "He just didn't want to come home."
She pulled free of Amber's grasp, and turned to walk away. Her heels snapped against the marble floors in a steady tap as the distance grew.
Paimon cast a look backwards, but then her expression was nothing but sympathetic as she caught Amber's eye.
"We'll talk later, okay? She's not mad at you or anything," the pixie whispered apologetically, and zipped to catch up with Lumine, leaving nothing but a glimmer of stardust and confusion behind.
Kaeya didn't know when he was relegated to the task of managing the feelings of young knights. Except perhaps he'd relegated himself to the job when Amber turned to him with that kicked puppy look on her face.
Well, he was going to do this anyway, so he knocked.
He didn't expect an answer. If anything, his planned contingency for a lack of answer was preferable, because at least he could retreat to his office and scheme. He wasn't sure what scheme he could possibly come up with that would be better than simply knocking on the Traveler's door and offering to talk, but he was sure one could never go wrong with an information-gathering campaign.
Instead, the door cracked open, and Paimon's large eye peeked out through the crack.
"Oh, it's Captain Kaeya!" Paimon declared, trying to sound cheerful. "Hello! Do you have a commission for us?"
"Actually, I just dropped in for a chat," Kaeya said, and pushed the door open. Paimon tumbled back through the air in surprise, before righting herself.
"Hey!" she snapped, indignant.
"Sorry, but I assume you wouldn't want to be here anyway," Kaeya said, grinning. "Seeing as there's a three course meal waiting for you in my office?"
Paimon's eyes went wide, and she cast a look at the shadows of the apartment, torn between her loyalties to the Traveler and her own stomach. In the end, her first master won out.
"Well, alright," she said, blatantly accepting bribery. "But..."
She reached out and grabbed the edge of Kaeya's cape, looking far more serious than Kaeya had ever seen of her.
"Um, I think you should ask her about her brother," Paimon instructed, her voice low and her gaze darting nervously.
No, not nervous. Concerned. Typical of Paimon to always say the obvious, but he couldn't say it didn't come from a place of caring.
Kaeya nodded wordlessly, and Paimon released his cape, disappearing down the hall. He closed the door behind her, feeling oddly furtive about this entire situation.
Emotional support was not part of his job description, he kept telling himself. Knowing people's emotional levers, how to manipulate them, what made them tick, that was one thing. But he had never had a knack for comforting people in times of emotional turmoil. Diluc could vouch for that.
Nonetheless, he persisted.
The sun had slipped past the horizon, and left the world in that anemic state of twilight that was not quite proper night yet. Outside, the lamps were just being lit, but it was much darker inside, the shadows already pooling in corners. Kaeya did not mind the darkness so much. He could see a fair bit better in the dark than most people.
He had never been inside the Traveler's quarters, but the contents did not surprise him overly much. It was cluttered; books occupied most surfaces, some from the library, others clearly acquired in Liyue. Other miscellany included dusty relics, little trinkets and the odd crumpled paper. It was an accumulation of items, the accretion of days mostly spent adventuring, but not the kinds of items that made up a life. If she were to pick up and go home one day, were any of the items here things she'd take?
He spotted the Traveler by her silhouette. She sat on the padded window sill nook at the far end of the sitting room, looking out over the view. It was mostly cobblestones and hedges, nothing truly interesting, but Kaeya supposed the only thing that recommended the spot was that as long as she was looking out the window, she didn't have to see the room.
He bypassed the missing person posters abandoned in a loose stack next to a low table, and made certain the floorboards squeaked to announce his presence as he approached. She still did not turn around, but as he stopped behind her, he could see the reflection of her face in the glass. Again, that blank mask.
He cleared his throat.
"I'm fine," she said.
"We're lying to each other now?" he retorted, feigning shock.
There was a long moment of silence before she twisted around, just enough that she sat parallel to the window, with her back against the wall. The nook itself was not very wide, and her knees were bent to fit, but it was quite deep, and Lumine was a slim girl, so Kaeya eased himself down onto the edge of the seat, back against the opposite wall of the nook. She crossed her arms, probably trying to look stern, but mostly she just seemed to be hugging herself.
"Do you want," Kaeya asked very seriously, "for me to go beat up your brother?"
Lumine's jaw fell open, and she looked at Kaeya with a decided lack of blankness on her face, frozen in that posture for several seconds, until finally she burst into laughter. Kaeya found himself grinning as her shoulders shook with each heaving guffaw, her entire body snapping from the tension that had it tightly wound all day and erupting into the first emotional outlet it was allowed. When the wheezing heaves started sounding more like sobs, Kaeya fully expected it, and took Lumine by the shoulders, drawing her close. It was not quite a hug, but he leaned her against his chest, and she curled her legs into his lap, and they stayed like that until her body stopped convulsing with laughter, or sobs, or any combination of both.
Though, even after Lumine stilled, she did not pull back, instead turning her face into the fur of his cape. She didn't say anything, and Kaeya would have been fine assuming she simply didn't want to talk about it, but he also knew some people merely awaited to be prompted. He knew some people actually did want to talk about the terrible things that happened to them.
Kaeya still didn't feel adequate to the task, but what was he, if not good at pretending? His fingers played with the ends of her blond hair at the back of her head, not quite brushing against the nape of her neck. He thought about rubbing her back, the way Adelinde or Master Crepus would do for him on the few occasions he'd been sick as a child, but felt too awkward to go through with it. He leaned his cheek against the top of her head instead, breathing in the smell of flowers and the clinging scent of old dust. She'd been in a ruin somewhere recently, and he filed away this fact out of habit.
"I'm sorry," Kaeya said. "Whatever he did, whatever he said to you, I'm sorry."
Was this what he would have wanted to hear after his fallout with Diluc? He wasn't sure. Lumine didn't stir.
"He just... wouldn't come home," she whispered.
Kaeya didn't understand, so he remained quiet. He took this tactic often, during interrogations, when he was simply fishing for information. People had the tendency to fill the silence. This was the same thing for the most part, wasn't it?
"I thought," Lumine continued after a while, "that whatever happened, we'd always feel the same about each other. That we'd always be the most important people to one another. We always have been. But he..."
Kaeya's fingers moved up from Lumine's nape to card through her hair, the motion even and gentle, like petting a wary cat.
"He has other things that matter more to him, I guess," she concluded pathetically.
Kaeya huffed.
"His loss and not ours, then," he said.
Lumine pulled back to look at him. Somewhere outside the window, a lamp had been lit. Night was fully upon Mondstadt, but the steady glow of lamplight came instead, gilding orange highlights onto her cheekbones, her forehead; the side of her nose. Just enough of her face that the anguish was easy to read.
He shouldn't have let himself grow soft over it, but Kaeya couldn't help it. His fondness was hard to earn, but even more difficult to shed once earned. Somewhere along the line, he had shuffled the Traveler into the list of people who had earned his loyalty, though naturally he would never say so to any of their faces.
"I have a feeling you didn't mean for him to come back to Mondstadt when you said 'home'," Kaeya remarked.
Remorse was just as easy to read on her face, especially when she looked away fully, and turned her entire face towards the lamplight.
"It could have been Mondstadt," she said, defensive yet subdued. "It could have been anywhere. I didn't think about where at the time--"
"But you would have left us all without a word for your brother's sake, hm?" Kaeya asked, though without much accusation. "If it came to that. If that was what he asked of you."
She lapsed into silence again. Did not deny it. Kaeya sighed, because he hadn't come to make her feel worse.
"In the moment, it must have felt like the only thing you wanted," he hazarded a guess. "The only thing that mattered."
Lumine nodded slowly. "But it wouldn't have solved anything." Then she gave a bark of laughter, devoid of any humor. "I don't even know what could possibly have solved any of it."
"Now what do you think there is to solve here?" Kaeya asked.
"I think whatever is at the heart of it, it happened when Khaenri'ah burned," Lumine said, and the words made a rushing sound rise to Kaeya's ears, like that of crashing waves superimposed over the entirety of his perception. Blood was rushing to his head. His heart was beating too fast. He simply hadn't been expecting it, that was all.
"...Oh?" he managed, his body continuing automatically along its track even as inside it felt as though his mind peeled off to have its own separate experiences of that moment. He felt the smile spread on his face, unnatural and forced. "And what has it to do with Khaenri'ah?"
She backtracked then, began the story with a man named Dainsleif. Kaeya knew the name, he even knew the face attached, but he had never connected the stranger who'd passed through Mondstadt with the figure of borderline myth from Khaenri'ah's past. Why would he? What was more likely, that some zealous parents had picked a name from a book, or that the Twilight Blade himself had betrayed the last royal family of Khaenri'ah, and now wandered Teyvat like a deathless ghoul?
As the story progressed, Kaeya found any number of alarming details to become concerned about. It was scattered, like Lumine was relaying a bullet point list of most to least important details instead of events in chronological order, but it was not a terribly long or complicated story when taken as a whole. It merely contained a distressing mix of facts.
He stayed quiet long after Lumine finished speaking, digesting everything with a sluggishness that was not typical of him. But how might one react to such news?
The current situation, then. He needed to take stock.
"So, your brother and Dainsleif have departed through a portal, and you do not know where they are," Kaeya said.
Lumine nodded.
"But you expect to see your brother again."
"Of course."
"And Dainsleif?"
Lumine pulled a face.
"You and Aether both," she muttered, more to herself. "Why does Dainsleif even matter?"
"That... is hard to explain," Kaeya admitted. "He's from Khaenri'ah."
"And? So? What does it matter to you personally?" she persisted. Tired and frustrated, and now her sadness was turning into anger. He didn't hold it against her that she was lashing out.
Kaeya smothered a rueful laugh, reached instead for his eyepatch. This was something he couldn't reveal with words. A juncture in the road, and he was making the same choice that had lost him his brother. Except now he did it with past experience already demonstrating what a terrible idea it was.
He pulled off the eyepatch. The right side of his face was away from the window, drenched in shadows, but she would still be able to see it: the touch of Khaenri'ah's corruption around his eye; the cancerous blue glow etched unto his body, waiting in his veins to claim him for the Abyss one day. Years or decades down the line, but still a surety.
She was quiet and motionless, so devoid of reaction that Kaeya thought perhaps she didn't see it or didn't understand it at first. But when she finally moved, it was nothing dramatic, only her hand rising slowly to cup the side of his face.
"Does it hurt?" she asked in a hushed voice.
"Of the two of us, I suspect you are the one in the greater pain at the moment." Which was not a no, but also not untrue. It was less a pain, and more a transitory ache. Maybe, half the time, he was even imagining the sensation of that vein of evil digging deeper in his skull, its roots spreading.
He looked into her face, trying to identify the moment when it would shift into realization and hostility, trying to superimpose his memory of the same on Diluc's face when Kaeya confessed.
But there was nothing but a softness in Lumine's face. A softness in her touch. When Kaeya swallowed, it was past the burning knot in his throat that he hadn't even noticed. Kindness always cut him deeper than hatred.
"So what now?" he asked, covering her hand with his own, holding it to his cheek like a lifeline.
"Now?" she repeated faintly. "Now... I suppose we are in this together."
He didn't quite understand what that entailed yet, but he nodded. Together. Yes, once they had pooled their secrets together, how could it be otherwise?
"Together, then," he agreed.