Am I the only one thinking she's calling him "bandito"? Angel always calls me "bandita", which is a playful term. The English equivalent, other than the obvious literal translation of "bandit" would be someone like who loves sex and/or is playful. The only close word I can think of right now for a female would be vixen or seductress, and the word for a male escapes me... Okay, I guess I've let you all in on a little secret, haven't I?
Bandito doesn't always have to be referring to sex...it could mean something like "little bugger" in a good way. A real good English equivalent word escapes me.