There was a kind of rhythm to the bustle of the tavern, a drunken dance, if you will. Diluc Ragnvindr hesitated to refer to such an atmosphere as elegant, though Angel's Share was at least more composed than most other taverns, if not just because patrons knew better than to cause a serious ruckus. Yet, even for closing hours, it was quiet. A key instrument was missing from this band of slurring customers, the taps against floorboards and the clinks of glasses. It lacked that annoying, raspy laugh of Kaeya's. For better or worse, Kaeya had become part of the experience at Angel's Share, despite him being a Knight of Favonius and Diluc's distain for them. The man was quite punctual when it came to drinking, to the point where it was a wonder if he was just as punctual about his work. Thus, it felt odd for Kaeya to not be there. Diluc, however, knew why he wasn't.

Kaeya's birthday was in three days, and Jean stopped by Angel's Share to confide in Diluc about her secret plans for a surprise party. As Acting Grand Master, she assigned various tasks to Kaeya in an attempt to keep the cavalry captain preoccupied so he wouldn't notice the party preparations happening. Diluc had scoffed to her, "You know he'll figure it out anyways."

Diluc remembered the smile that spread over Jean's features, "It is very likely. But there is still the hope that we just might surprise him."

This brought a swirl of nostalgia in his chest. Diluc remembered him and Jean being much younger and plotting very similar surprises for Kaeya, before any of them were knights. At that time, Diluc and Kaeya were still brothers, living at the Ragnvindr manor, occasionally visited by their good friend Jean of the Gunnhildr family. Despite their efforts, Diluc and Jean almost never managed to surprise him. Even as a child, Kaeya was notoriously observant.

But that was years ago. This time, Diluc had very little involvement in the surprise party, to the point where he wondered why Jean was telling him about it. Her excuse was that Diluc could help distract Kaeya should he actually find time to go to the tavern. But the reality was, Jean came to invite Diluc to the party.

Diluc recalled his discomfort. He adjusted his gloves, feeling a knot in his chest. Jean's sky-blue gaze just looked so hopeful. In that moment, it wasn't about a knight's party, it was about his once-adoptive brother's birthday. Diluc tried not to visibly stir. He answered as politely as he could, "I appreciate the offer, but I…cannot guarantee my attendance."

The disappointment in her eyes left a weight on his shoulders. The burden worsened when she smiled with a gentle acceptance, "It is entirely understandable. Please do keep the date in mind, in the chance that you may be available. It may be a nice change of pace. We would look forward to having you, and—" Jean stopped herself from saying something and instead finished, "—I hope you have a good night, Master Diluc."

The conversation left him in a swirl of emotions. A part of him lamented the years it had been since he attended a birthday party for Kaeya. Another recoiled at the thought and forced away the nostalgia. He was frustrated that Jean kept persisting in these kinds of invitations, though she presented them softly and with her heart in the right place. But was she really certain that Kaeya wanted to see him beyond his shifts at the tavern? Bitterly, Diluc thought, If he truly wanted to see me, why not say so to my face?

A tug in his heart answered, I haven't exactly approached him either.

But Diluc never felt he had a good enough reason to seek out Kaeya. The only exceptions were to utilize the man's intelligence networks, which included some rather dubious contacts that a Knight of Favonius shouldn't technically associate with. Diluc would have rather kept their interactions strictly to business. It would be simpler. Yet, the past refused to stay behind.

'It may be a nice change of pace,' Jean's words went through his mind as a light breeze. It gave him pause.

Diluc hadn't forgotten about Kaeya's birthday, he couldn't. He even had a gift planned out, though he had no intention of giving it in person. He had anonymous birthday gifts sent to Kaeya before, because his guilt refused anything less. But could he give it in-person this time?

His stomach lurched at the thought, and Diluc nearly slapped down the glass he was polishing. I couldn't. He told himself that he needed to be ready in case if the Abyss Order or the Fatui stirred trouble, that he didn't have time to attend. But that's not the real reason, is it?

No, the truth was it felt strange, intimidating even, to imagine attending something as simple as a birthday party. Diluc couldn't just pretend as though things could be normal between him and Kaeya, much less how it used to be before. How could they? After that horrid night of Diluc's eighteenth birthday? After Diluc had left Mondstadt and left Kaeya for three years? No. Instead, Diluc resolved to keep things simple and would have his gift delivered, just like always.

While Diluc mulled over things, he caught himself polishing the same empty glass for the past few minutes. He sighed, clacking the glass against the counter. It was time to close anyways.

Loitering customers were curtly dismissed. This left Diluc and his employee Patton to close. Seeing that Patton no longer needed to wave new patrons over, his task became scooping up the barely conscious drinkers, usually Nimrod and Quinn, and safely relocating them out the tavern. Diluc set to work in cleaning and straightening what he could to ease Charles's shift tomorrow. The mess that patrons left behind was something of a marvel in its terribleness. Thankfully, that made the clean tavern all the more satisfying of a sight, and it helped clear his head. Glasses set, chairs arranged, lamps extinguished, and, finally, Diluc stood on the small back porch outside, locking the last door with a click, dropping the key in the depths of his coat.

The night air was refreshing, blanketed by pale, blue moonlight. The city had mostly gone quiet, with only the murmur of people from their windows, the footsteps of a patrolling knight or a wayward frog that had made its way past the walls. All the noises seemed distant, giving it a dreamlike quality. An icy cold clasped the air and clung to the back of his neck. He was aware of a presence behind him.

Diluc sharply turned. The space between the wall and the stacked barrels didn't allow room to summon his claymore, but Diluc had his fists and Pyro Vision at the ready. A dark figure indeed awaited him on the porch steps, but he recognized her. It was Sister Rosaria. She had him cornered, her form as still as a cat before the lunge, and her crown of spikes cast a sinister shadow that stretched out for him. It would have been tempting to think she would attack. But Diluc knew her well-enough; if Rosaria wanted to ambush him, she would have done so already.

He relaxed and crossed his arms, "Sister Rosaria. I don't suppose you've come for a drink. I've just closed shop."

She clicked her tongue, "I'm not here to drink. You're ridiculously elusive for a businessman. I knew coming here would be the best way to finally catch you."

Diluc felt wary. He thought, She wanted me alone for some reason. Otherwise, she could have approached me at the counter. Diluc regarded her carefully but kept his voice casual, "Oh? Was there something you wished to speak with me about?"

"I'm not here to chat," Rosaria answered. "What I need is a Cryo Regisvine dead." She gestured in annoyance to her Cryo Vision, which gleamed icily in the dark and would've done little against a Cryo creature. She finished, "And I need it done fast."

Diluc caught her meaning but he made no move to accept her request.

"Why do you need me to defeat a Cryo Regisvine?" Diluc asked. He was not one to argue killing monsters, but Rosaria's behavior was suspicious.

She glanced away and, in her eyes, there seemed to be a flicker of…bashfulness? Diluc wasn't sure if he'd ever seen that expression on her. She cleared her throat and answered, "I need Shivada Jade. It's…for a gift."

Diluc rose his eyebrows, earnestly surprised, "A gift? For whom?"

Her gaze bit him and she snapped, "Is that really important to know? Are you going to help or not?"

Diluc paused. The years of etiquette carefully ingrained in him by his late father reminded Diluc it wasn't polite to pry, but fighting a Regisvine was not a request Diluc wanted to blindly jump into. He carefully responded, "I may be able to, but it depends; when would you need this done?"

Rosaria made a disgruntled noise. She crossed her arms and answered, "I need it within the next three days. The sooner, the better."

Diluc furrowed his brow. Something about that sounded familiar. A gift for someone within three days from now? Diluc flipped through his mental calendar and considered who Rosaria might know. Diluc and Rosaria weren't exactly close. As far as Diluc knew, this gift could be one of her fellow nuns or might not even be anyone from Mondstadt. Their only mutual contacts were regulars at the tavern, like Venti or Kaeya.

A realization struck Diluc.

The words were out of his mouth before he could stop them, "Is this gift meant for Kaeya?"

Her eyes widened, looking startled. It was quickly replaced by irritation and a flush in her ashen cheeks, "So what if it is?" Rosaria had a scoff claw through her throat and she turned away, "If you're not helping, then we're done here. I don't have time to waste."

"Wait," Diluc sharply called, with a light panic in his heart that she would run off. "Wait, I didn't refuse."

Rosaria stopped halfway down the steps. She turned her head and her eyes slid to him like cautious knives.

Diluc continued more calmly, "I apologize, I didn't mean to pry. If you'll allow me, I can help you. There should be a Cryo Regisvine in Falcon Coast that's only a day's trip away."

She didn't answer at first. A passing wind tapped a hanging lantern against a building. Rosaria faced Diluc again and she responded, "I don't know if you're factoring this in or not, but I'm going as well. I planned on collecting the jade personally. I just need a Pyro wielder to help take down the stupid flower, and you happen to be the best candidate."

"I assume you're rather experienced with traveling outside the city, so I don't imagine that effecting the timetable much," Diluc answered. He heard second-hand accounts of Rosaria leaving Mondstadt city to quash trespassing Fatui soldiers in the unforgiving cold of the neighboring Dragonspine. There was no doubt in his mind that the trip to Falcon Coast would be far more comfortable in comparison. He asked, "Though, I'd like to ask, do you have horse-riding experience?"

She crossed her arms, "Not really."

Diluc hummed to himself, thinking it over. He said, "That's fine. Even on foot, it should still take a little over a day."

Rosaria asked, "When can you be ready to go then?"

"I still need to return to Dawn Winery to settle some affairs. Let's meet outside the city gates at six, tomorrow morning. If we're quick about it, we should be able to retrieve the jade and return by nightfall."

Rosaria clicked her tongue. She bit her thumb and muttered something under her breath. Diluc managed to overhear, "…been better to just go tonight. Now I gotta get up early like it's for a stupid morning service…"

Finally, she said to Diluc, "Alright, fine. See you then."

Without so much as a goodbye, Rosaria turned and left. The muted colors of her clergy uniform allowed her to melt into the dark, appearing as no more than another shadow.

Diluc stayed on the tavern's porch, trying to sort his thoughts. Rosaria wants Shivada Jade from a Regisvine to give Kaeya for his birthday. He supposed it wasn't too surprising. Rosaria and Kaeya seemed to spend a lot of time drinking together, and some of their conversations implied that they regularly saw each other outside the tavern as well. But to go out of her way to fight a Regisvine? That didn't seem like something that someone would do for merely an acquaintance or even a friend. Rosaria especially had expressed an aversion to what she considered 'overtime'.

You're prying again, Diluc chided himself.

There was still a quiet question, lingering in his chest like a firefly. Why did he accept her request? After all, he was supposed to be ready in case if the Abyss Order or Fatui caused trouble. The Cryo Regisinve counts as a threat to Mondstadt as well, Diluc told himself. Killing it tends to decrease the number of Cryo Whopperflowers endangering adventurers. And Rosaria wouldn't have asked me if she didn't sincerely need my help. But he knew real reason, buried in his heart.

Diluc quashed further thoughts. He couldn't allow his mind to wander so much. It was dangerous to get distracted. He sighed and stepped down the porch. He refocused his attention to think of what he needed to do to clear his schedule for tomorrow.

After talking to Diluc, Rosaria only pretended to leave. She hid behind a stack of barrels and melted with the shadows, secretly watching. Her reasoning was, people tended to act differently when they thought they were alone.

Diluc didn't seem to do much, aside from lingering on the porch, staring at the floorboards as he swam in his thoughts. The night around him was blue and black, and he would've blended in with his dark coat if not for his fiery red hair. It was hard to tell what he was thinking, though likely it was about their discussion. His thoughts seemed to take a turn he didn't want, as he shook his head with a deep exhale. He finally left the porch and headed off.

Is he rethinking the agreement? Rosaria couldn't say for certain. I still can't believe he actually agreed. From what Rosaria understood, Kaeya and Diluc had a falling out years ago, and Diluc left the Knights of Favonius while Kaeya stayed, all on the same day that their father was killed by the monster Ursa the Drake. Apparently, things weren't as bad between them lately, since Rosaria saw Kaeya drink at Angel's Share all the time, including when Diluc worked the bar. Though their conversations were usually anything but cordial. Diluc practically breathed insults about the knights, and every other word out of Kaeya was an underhanded quip towards him. As a result, Rosaria didn't want to risk Diluc refusing to fight the Regisvine because it was for Kaeya, so she tried to hide the fact. Yet, he found out and he still agreed to it.

It's a dangerous job that benefits someone he dislikes. What does Diluc have to gain by accepting? Rosaria tried to consider. Unfortunately, she didn't have an answer. And, despite all her suspicions, Rosaria wasn't going to turn Diluc away. She needed that Shivada Jade.

I guess I should head back then to get some sleep, Rosaria thought, begrudgingly recalling the early morning rendezvous. With an annoyed huff, Rosaria made her way back to the Favonius Cathedral.

The route to the church was always longer than away from it, as Rosaria meandered up the dozens of stairs and swept through the shadows of buildings, almost as if looking for something else to preoccupy herself with. But it was a quiet night, with no suspicious figures prowling aside from herself, and Rosaria quickly had the looming shape of the Cathedral before her. The moon shone against the building, causing its white body to glow, while cooling shadows covered the sides not touched by the moon. Rosaria didn't bother going anywhere near the large front doors. She slid to the shadowed side and she climbed up the ornate stone carvings and window arches with little regard for the hundreds of years' worth of history attached to them. Once she reached the floor where the sleeping quarters sat, Rosaria silently pried open the window and slipped inside.

The corridors were normally dark at this time of night, but the orange glow of a candle bobbed around the end of the hall. Rosaria wasn't one to show fear, having seen things that most people should count themselves fortunate to have never seen. But she broke into a cold sweat at Sister Victoria's approach and darted from the candlelight without a noise. Rosaria had to take the long way to her quarters to evade Victoria, because if she was caught up late again, Rosaria feared she would be charged choir practice and morning prayer for a whole week.

Not until she was back within the confides of her sleeping quarters did Rosaria relax. Before settling in completely, Rosaria went to her desk, moving aside the half-read religious texts to review a map of Mondstadt. She noted Falcon Coast and the cave of the Cryo Regisvine that Diluc recommended. It was a good choice and the same one she had in mind, since the only other Regsvines were much farther away in Liyue. Rosaria's fingers brushed against a calendar and then lingered on November 30th, Kaeya's birthday.

Rosaria didn't have extensive experience with birthdays. She rarely celebrated her own since, for the longest time, each day was simply another day to survive. But since she joined the clergy, the sisters had tried to change that, especially Barbara, who would insist on at least singing her a birthday song each year. Rosaria supposed it was nice at times, especially since even Victoria tended to be laxer with her schedule on that day. However, Rosaria couldn't stand the thought of having a birthday party and refused the sisters' offer each time. She didn't like the idea of being the center of attention, where she couldn't slink off into the shadows whenever she wanted. Simply celebrating with drinks at the tavern was enough for her.

Though, her stance on birthdays steadily changed, and that was largely due to Kaeya.

He was a funny sort of guy. Kaeya was a knight, but he casually drank alongside criminals. Almost everything he said was an elaborate half-truth, but everyone trusted him. Much of what he did was off-the-record, but, instead of conducting secret deals that undermined the city, he protected the innocent and rooted out villains without anyone being the wiser. She found his paradoxical lifestyle amusing and related to it in a sense. Rosaria rarely admitted such things, but she enjoyed spending time with him, whether it was at the tavern or hunting criminals together across Mondstadt.

Kaeya put up a lot of masks, but once she got a glimpse of the true man beneath, she allowed him to see beneath her own veil. His gifts for her certainly reflected their growing bond. It started with him buying her extra drinks. Then it became new camping equipment and weapons to replace what Rosaria had worn out. The most "Kaeya" gift that he'd given her so far was a lead to Treasure Hoarder camp, which turned out to have no Treasure Hoarders, an unlocked chest containing bottles of her favorite wine and a lovely view of the sunset that bled into an even lovelier view of the night.

Amidst her pleasant memories, Rosaria felt a small sting at her lack of gifts for Kaeya. Paying for drinks barely counted. He'd tease her, but never pressured her into the idea. That only spurred her to try returning the kindness somehow. It felt like the perfect opportunity presented itself when Jean discreetly approached Rosaria to invite her to Kaeya's surprise party. But finding a meaningful gift turned out to be a more mysterious enigma than Celestia itself. Rosaria believed in an equivalent exchange, an eye for an eye whenever it applied. But how could she possibly repay countless precious moments like left a lingering warmth in her? After much time toiling and scraping for answers, Rosaria finally set her sights on the uncommon Shivada Jade, which only came from incredibly dangerous creatures like the Cryo Regisvine. Its power could boost his Cryo and maybe even help protect him when she wasn't there to.

Having removed her coif and laid down in her bed, Rosaria had a certainty in her heart. I'm making it my job to give Kaeya something special for his birthday. And I always see my jobs through to the end.

CatCrescent: This story has been a couple months in the making to help celebrate one of my favorite Genshin characters, Kaeya. Ironically, he doesn't make an appearance in this chapter, but he will show up at the end of the story. I hope you enjoyed this first chapter and I'd love to hear your thoughts! This is one of my most ambitious projects yet, and I'll be posting a new chapter each day. It was originally just supposed to be a simple Rosaria/Kaeya about Rosaria trying to find a birthday gift for Kaeya, but then it kind of ballooned into an attempt at a Ragnvindr brother reconciliation story. Plus, Rosaria and Diluc are both very cool, secret vigilantes and I want more excuses for them to collaborate. Come back tomorrow for the next chapter!