And the band started leaving, 'cause they all started bleeding

The story:

At the End-Of-The-Year party at school, we were playing Rock Band, I made the mistake of being the singer and choosing this song. I sang it with eyes closed, because I was pretty confident I knew the real lyrics...only to open my eyes and discover all my classmates looking at me weird. I always did think that that must have been one heck of a ballroom blitz to make even the band start bleeding!