KaeLuc

Kaeluc is the family and slash ship between Kaeya Alberich and Diluc Ragnivindr from the Genshin Impact fandom.

Canon
About Kaeya and Diluc's first meeting, it was when they were around 12 years old, when Kaeya was adopted by Crepus Ragnvindr aka Diluc's father.

They seem to have a love/hate relationship, especially after the events that happened regarding Crepus's death: Kaeya revealed to be a spy from Khaenri'ah, so they fought and Diluc left, while Kaeya received his vision.

Quotes
"Kaeya? You can only trust half of what he says... at best."

- Diluc's voiceline about Kaeya

"You want to know what's in my glass? It's... grape juice. My drink of choice."

- Diluc's voiceline about favorite food

"Diluc? He was cute as a young lad. But nowadays he just seems to be in a world of his own... Overall, not much fun to hang out with."

- Kaeya's voiceline about Diluc

"I can't believe that some people actually drink grape juice... if they had a little more patience, they would find that it ferments into the most exquisite wine. Hmph. So unromantic."

- Kaeya's voiceline about least favorite food, mocking Diluc

Fanon
This ship is one of the most popular in the entire game, both for the content that leads to the ship and for the hate it gets:
 * As said above, Kaeluc is a ship that viewed in a western environment could be considered incest, but in a eastern environment (as meant to be given the company's location - China), it's considered as M/M ship.

Many fanarts, comics and fanfictions have been created for this ship and much likely those are contributing to keep the ship alive.

Some may ship them in a romantic settings, other may see only brotherly love.

Fandom
Artworks Fanfictions

Trivia

 * Both of them are currently around 20~24 years old (not confirmed, but in the manga Diluc was 18 when he ran away from Mondstadt and came back only after 4 years. These events happened before the actual current lore)