Baby your a slut, it's a put on

The story:

The first time I thought the lyrics were "baby you're a slut" was when my then boyfriend was singing the song to himself. I smacked him and he said, "what?" "I can't believe you just sang that!" "But those are the words to the song." Then once day it came on the radio and he started singing again-only this time I realized what he was singing. I had to tell on myself. All this time he had wondered why I had smacked him that one time.