Cross-posted on AO3

Day 23: "Don't Look"

If there was any way that Diluc had expected today to end, it hadn't been this way.

He had spent many sleepless nights searching for Kaeya ever since the night the captain had mysteriously disappeared from his barracks. Upon close inspection, they had concluded that an Abyss Mage must have broken into the man's room and attacked him in his sleep.

Ever since that day, Diluc had hardly slept and had taken to searching anywhere he could think of that could be an Abyss Order hideout. After months of nothing, he had finally caught a whiff of a trail.

Well, more like the Traveler had.

He had run into Lumine completely by chance while wandering around Wolvendom. She had apparently been visiting that wolf-boy friend of hers when she had spotted him walking around almost listlessly. After so long without a trace, Diluc had begun to lose hope of ever finding his brother. He had nearly collapsed in relief when the Traveler used her own Elemental Sight to track down the Mage.

They had wound up back by Starnatch Cliff and had found a hidden dungeon built into the side of the cliff that they had easily broken into. He was thankful that the Order never seemed to get smarter and find better hiding places or security. It only made their mission so much easier.

It hadn't taken very long to take out the Mages and they were soon moving deeper into the domain. There were some tricky puzzles in the way, but it didn't slow them down and they finally made it to the final door. Diluc cautioned the Traveler back and slipped through the door open, expecting to see more monsters that would try to delay their rescue mission.

What he saw instead made him almost want to run back out of the room.

A large creature was crouched in the corner, its head bowed low. It appeared to be breathing, so Diluc could definitely say that it was alive. It was dressed in dark blue robes that split into several tails around the waist and wore matching pants and black shoes.

It shifted at the sound of his arrival and Diluc readied himself for a fight.

It wasn't until it rose and turned around that Diluc finally noticed how much bigger than him it was. While it wasn't bulky, but it was tall, towering over Diluc by a few feet. Its aura didn't give of the usual threatening feeling that he was used to coming from monsters.

Just as it caught sight of the wine tycoon, however, the creature quickly turned back around, curling itself into a corner as if to make itself as small as possible. It almost reminded him of when he used to think that of he couldn't see Adelinde and Father while playing hide and seek, then they couldn't see him.

It was odd behavior coming from a monster.

He's brought back to the present by Lumine coming up beside him. She looked as surprised to see the creature as him.

"That's. . ." she started, only to be interrupted by Paimon popping up on her other side.

"Isn't that what Dainsleif told us about?!" the tiny fairy creature exclaimed. She quickly adopted a thoughtful pose as if she was trying very hard to remember something. "What was it that he called them? Paimon knows he warned us about them!"

"An Abyss Herald," Lumine said, her voice just starting to waver with nervousness. "Dainsleif told us about how Abyss Heralds were a lot stronger than your average Abyss Mage."

Both girls didn't notice how Diluc had perked up at the mention of the strange customer from Angel's Share. He had known about these creatures? The only members from the Abyss Order that he ever had the unfortunate displeasure of meeting were the Mages and now he was learning that there were apparently even stronger monsters in the organization.

Today was just filled with unpleasant revelations.

The three's attention was brought back to their situation when the Herald started making loud distressed noises. It was ramming its head against the wall violently and they were all startled by the monster sounding like it was crying.

Without hesitation, Lumine and Paimon rushed towards the monster, ignoring Diluc's call. However, they didn't get very close before they were forced to jump back by a spear of ice launching at them.

"What was that for, you big meanie?!" Paimon screeched.

The only response she got were louder sobs. The Traveler was starting to look worried, clearly not liking that the Herald was so distressed. Something in her was telling her that she couldn't leave the creature alone, not while it was in this condition.

A hand on her shoulder has her turning to see Diluc giving her a stern expression that wasn't quite a glare.

"Stay back for now," he said, dismissing his claymore. He knew that he would only get an earful from her if he attacked it now since the monster was clearly non-hostile. "It appears to use Cryo, so my Pyro is better suited here."

His life was so backwards right now. Since when did he help anything from the Abyss Order. Hopefully, this could at least end in getting some info out of the Herald if they played nice.

His approach wasn't easy. The Herald reacted even stronger to him than it had to Lumine, flinging one Cryo spear after another. While dodging them was easy, it was annoying how it kept slowing him down. By the time he was right behind it, they had made a mess of the room, the spears sticking out of the floors, the walls, and the several pillars. The attacks had been relentless, but ultimately harmless by how far off they usually were.

When he finally went to put a hand on the creature's shoulder, it suddenly shot around to look at him. While he couldn't see the face past the helmet, he did spot something that surprised him. Just inside the helmet was what looked like a single lilac eye staring back at him.

A very familiar eye with a star-shaped pupil.

" Kaeya. . .?"

The breathy question was enough to shock the monster – his brother – into action. A sharp blow to the stomach had him shooting backwards with a pained grunt. He hit the ground with a hard thump that knocked the wind right out of his lungs.

"Master Diluc!"

Lumine and Paimon were right by his side in an instant. Lumine summoned her blade and moved to rush forward, but was stopped when Diluc grabbed her wrist before she could get far.

"Wait!"

"Master Diluc, it attacked you!" she said angrily.

So much for wanting to help, he thought dryly.

"Lumine," he wheezed, "I'm fine. I just scared him."

"Him?" she asked, cocking her head curiously, all signs of anger disappearing.

"Uh, guys. . .?" Paimon asked skittishly, effectively catching the other two's attention.

The three turned back to the Herald and noticed that it had stopped flailing and was completely still, whimpering pathetically. Lumine still looked on edge like she was waiting for another attack and Paimon had ducked behind her, peaking over her shoulder cautiously.

Diluc felt his heart throb at his brother's pain.

". . .away. . ."

"Huh?" Paimon squeaks.

"Go. . .way. . ." the Herald whimpered. "Don't . . . look . . . at me."

He was beginning to cry again and Diluc wanted more than anything to rush over and pull his brother into a hug. Kaeya had been missing for several days, just shy of a week. In that week, they had turned him into this monster.

How long had he been locked into this room?

He had been in pain this whole time?

Was he in pain now?

All Diluc knew was that he wasn't leaving this domain without his brother.

A/N: This story was partially written on the 25th and finished on the 26th. I wrote a post about this on Tumblr after I heard a rumor about the Abyss Heralds and reread the prompt for this day. I apparently have a love for Kaeya turning into something, whether it be a monster, child, etc. and Diluc being very protective of him in the process.

In this case? Turned into a monster that hasn't even been revealed yet.