Kaeya Alberich was once a pirate, but after an accident where he lost his left eye, he decided instead to join a more noble service, becoming a knight of Favonius in a town called Monstadt. When he and his brother Diluc lost their father, Kaeya wanted to make it a point to be kind and protective of any children in his life and be a parental figure of sorts to those who had bad upbringings. Kaeya is cocky and sarcastic, often cracking passive-aggressive jokes.