When a girl generally wearing a tube top or even one of your friends who happens to look expecially slutty any given day appears to have taken a bath in "slut." On occastion a slut bath might not appear to have taken a bath in slut until you see her hitting on every boy at the party including your boyfriend.
"Get off my man, you slut bath."
"Wo, you had a slut bath didn't you?"
Person A: That girl looks insanely slutty.
Person B: Someone took a long slut bath.