My dragons have been named after the Castlevania video game series: Simon Belmont, Richter Belmont, and Alucard, son of Dracula.
My chameleons have been named after the Final Fantasy video game franchise lizard clan, called Mamool Ja: Gulool Ja Ja, Mamool Ja, and now Vedool Ja
I like to keep each species in a theme to tie them together, and clearly I am inspired by video game characters.
I'd recommend something personal to who you are. Movies, books, shows, games? Maybe just looking at him/her and the first name that comes to mind. Pedro? Francesca? Duke?