Cross-posted on AO3

Day 2: "I Can't Take This Anymore"

Diluc hadn't meant for any of this to happen.

The wine tycoon had just meant to drop in for a quick chat with Jean before he needed to head back to Dawn Winery before noon. While he usually wanted nothing to do with the Knights of Favonius, talking with Jean was always welcome. Talking to an old friend just seemed to calm him, though he made sure to subtly jab her to make sure that she wasn't letting her title get to her head or that she wasn't becoming corrupt like the others.

Of course, it would be during that calming atmosphere that the Calvary Captain would choose to walk through the door.

"Excuse me, Acting Grand Master -," he started. His mouth quickly snapped shut when he noticed who else was sitting in the office. His usual fake smile shifted, growing into a grin that Diluc was only too familiar with.

"Get out."

Simple and to the point. Diluc wasn't in the mood to deal with Kaeya's nonsense today. Or any day really, but he had been having an arguably pretty bad day already before the other had walked through the door.

The other merely snorted derisively as his eyes narrowed.

"Last time I checked, Master Diluc, this wasn't your office," he said mockingly. "I'm merely here to report to my superior."

Diluc felt something in him snap. He didn't have the time nor patience to put up with his ex-brother's tomfoolery. His irritation was now through the roof and he couldn't be bothered to reel it in. When his mouth opened, he almost immediately regretted what came out.

"A Khaenri'ahn has no business being a knight in the first place,Sir Kaeya."

What he hadn't expected was for Kaeya to flinch at the sentence. However, the captain was quick to close off his face, his features becoming as cold and as smooth as his element. Without another word, he merely placed his report on Jean's desk and walked out the door.

"Kaeya, wait!" Jean jumped up from her desk and rushed towards the door. When she peaked out, the man was already gone. Turning to Diluc, her face looked like she couldn't believe what she had just heard.

"What has gotten into you, Diluc," she started, her tone incredulous. "What you said went way too far."

Not looking to be lectured, Diluc scoffed as he made his way out the door and leaving the office. Trying to ignore the guilt that was bubbling up inside him telling him to find the other and apologize, he left the knights headquarters and made his way towards Angel's Share. Maybe some work could distract him.

It wouldn't be until that night that he would realize how badly he screwed up.

Diluc was making his usual rounds around Mondstadt when it finally happened. He spotted a familiar figure walking towards the gate. Confused as to what he was doing out this late, he was quick to follow him.

He caught up to Kaeya just as he was about to cross the bridge.

"Sir Kaeya."

His words caused Kaeya to pause for a moment before he finally turned to look at him. Diluc was surprised to note that his usual fake smile was nowhere to be seen, but made sure to keep his face in its usual scowl.

"Where in the world you going at this time of night?"

Kaeya's eye simply narrowed.

"I don't think that any of your business, Master Diluc," the other's tone was neutral, almost flat. "Why don't you go back to your little night job."

"I think I have the right to know what is going on, don't you think?" Diluc was irritated at basically being told to shove off and it showed very clearly in the deepening of his voice.

Kaeya merely stared back for a moment before he broke out into laughter, but something was severely off about it. It startled Diluc to hear the other sound so broken like he was in some kind of morbid comedy show as his face twisted in a grotesque imitation of amusement. Just as suddenly as he started laughing, he stopped, his face twisted in a sad grin.

"I believe I no longer fall under that category; wouldn't you agree? Just turn around and pretend you never saw me."

"I don't think so," Diluc said as he tried to walk forward.

Tried being the keyword.

When he moved to take a step forward, he found himself frozen after the first step. Confusion and anger twisted together as alarms started going off his brain. He didn't know of any Vision that could freeze someone in place besides Cryo, but he didn't see any ice. His attention shifted when he heard a voice he didn't recognize.

"I'm sorry for being so late, Your Majesty."

Kaeya turns to their new arrival, moving just enough for Diluc to see them. The man is wearing a completely black ensemble with shoulder-length light blond hair and a black mask that covered almost half of his face. He looked just as pale as Diluc, but his single pale blue eye had the same star-shaped pupil that Kaeya's had.

"On the contrary," Kaeya said lightly, "you're just in time, Dainsleif."

Diluc watched in shock as Kaeya's face softened at the newcomer as the other walked up to him. Taking the captain's hand into his own, Dainsleif lifted the hand to his lips and gave a gentle, practically reverent kiss to the knuckles.

"Are you ready to leave, My Liege?"

The younger man took a breath as if to steady himself as he turned to give Mondstadt one last look. The main road leading to the gate was still empty, but he had no doubt that there were still people up and wondering about somewhere in the city. The bright light from the portal was going to attract people's attention, so he knew they would need to leave quickly.

When his gaze met Diluc's, the tavern owner could practically see something in the shift before he looked away. He seemed to hesitate for a moment before he turned and passed Dainsleif as he made his way towards the portal.

"Kaeya!"

His brother stopped only a few feet from the portal, barely turning to look at him out of the corner of his eye.

"Weren't you the one who said I was a threat in the first place, Diluc?"

No title. Diluc felt his heart begin to race as the seriousness of the situation seemed to finally be setting in. That this moment was real and that this was really happening.

"That's not-," he started but was cut off by the other.

"'A Khaenri'ahn has no business being a knight' wasn't it," his brother said. It was the coldest tone that Diluc had ever heard him use with him and he found himself flinching as his own words were thrown back at him. He could feel the color drain from his own already pale face. If he had a mirror, he was certain that he would have looked like a ghost from the stories he and Kaeya used to read together when they were kids.

Dainsleif definitely didn't look happy about the comment but didn't leave Kaeya's side, instead turning to follow him towards the portal.

"KAEYA!"

His desperate call was ignored as his brother walked through the gate and vanished. With a bright flash that almost blinded Diluc, the portal seemed to collapse on itself after the two went through and disappeared. Along with the portal's disappearance, Diluc felt whatever had been holding him in place release him, causing him to fall to his knees.

He couldn't bring himself to scream. He couldn't bring himself to cry. He could only stare at the spot where his brother had stood.

And now he was gone. Probably forever.

Diluc shook his head. No, he wouldn't let it end like this. Rising to his feet again he promised himself that he wouldn't stop searching until he brought Kaeya home.

"I promise, Kae."

A/N: The draft for this chapter was originally written on the 26th of January and transferring it to words was harder than I thought it would be. I'm planning to have the alt prompt out later today and maybe even typing up some new drafts for the other days later.