A usually secretive, sick and twisted activity/hobby that someone does, that KNOWS they shouldn't and feel downright ashamed for. Sadly, we all have them, including me.
Myself: *sighs* I like listening to Lady GaGa's "Bad Romance". Considering that I usually condemn mainstream music and I usually listen nothing but The Beatles, Led Zeppelin, Kansas, and other kickass bands, this is indeed a PRIME example of a guilty pleasure. -_-U