(1) someone who goes to a ton concerts. they don't care about ticket price or the musician; they're only there for the music
(2) someone who goes to concerts to try and have sex with the musicians' backstage
(1) a: hey man, look. she's always at a concert.
b: yeah, she's a concert whore.
(2) a: did you see that girl go back with -musician name-?
b: she's just another concert whore.