n. A bartender whose most important asset is his/her looks, rather than any skill in preparing drinks, remembering orders, resolving disputes, or dealing with belligerent patrons. May help to increase a bar's revenue from tips, explaining why so many of them manage to keep their jobs. Stereotypically female, but male examples are common. (Compare with the sci-fi term "bridge bunny.")
This term is also used to refer to a certain kind of drinker, but there are many other names for them.
My cousin's boyfriend works at the Louie's on Grand Avenue. He's a total bar bunny--he has to remind himself which end of a glass to pour beer into--but he's good at flattering insecure customers who feel like their lives have already peaked. So they leave big tips and all the employees benefit.