Xolph is a relative of Vesta, a teenaged cousin (of neither sex) whose homeworld is a kind of parallel 1990s Los Angeles. Their name is an anagram of "phlox", a flower with a similar color to their skin, and they're a deeply geeky person, fond of 16-bit video games, RPGs, and weird TMBG-esque music. You could call Xolph an "alien" and they'd agree it feels right, even if they're not actually from somewhere in outer space. They're just a cheerful weirdo.