On the way home tonight I was listening to an interview by Richard Kingsmill with Death Cab for Cutie. The bit I caught was about their song "Possess your Heart" which is a song I *love* and I just think his voice is so perfect for it. In any case, Richard was saying that when you first hear the song you think it's a nice love song and then on a few more hearings, you realise its actually a bit creepy.
I'm not sure which band member he was speaking to but he was saying that what he was trying to encapture in that song was empathy for a person who is obsessed but to show that the creepiness in the obsession is when that person doesn't know that they have crossed boundaries. And it's the fact that they don't know, that makes it creepy.