Yeah, I think the lyrics of he song 'closer' pretty much would be a reason why she wouldn't want you to listen to them. :]
I love the sick and twisted feel of the song, and the lyrics appeal to my crazy psycho side that I keep so well hidden. Oh, and the beat is awesome too.
Edit:
Here's awesome music by NIN that doesn't feature any lyrics:
YouTube - Just Like You Imagined - Nine Inch Nails (300 Soundtrack)