It started with an old RP character of mine from 18 years ago, a Drow named Khalith. "Khalith" is the Drow word for "courage." It's been a favorite of mine for years and been something I've stuck with forever. As for "Mateo" it just means "Matthew" in Spanish which is a shout out to my Latino roots and "Mateo" means something along the lines of "favored by god" and since I main Paladins, it made sense since Paladins are traditionally holy knights of some deity or another.