Well, I was told to post here by DT. Not sure why, but best guess is the user Slender Man.
I think it's because either me and him go to the same school, which is often the few times of day we can log on, or otherwise, he lives across the road from me, so IP's would be similar anyway.
Sorry, I don't have a link to his profile. I'll grab one when I can, but he only uses the site once a week when I'm not around or something like that.