Slender man, is a creature with no face. He is very tall, and always wears a suit. He peers through windows, and stalks people. He likes to kidnap little children, and do who-knows-What with them. :D
^ I think slender man was created in some sort of "Scare 'em" Competition in 2009. People created fake photo's, and it got leaked through the internet to freak people out. Now people have been creating rumors, and there are even Slender man sightings. Though i'm pretty sure it's all fake. :)
Yeah, I've heard of him. Never seen him in real life, and I won't. He's just another one of those stories that people like to make to freak their フレンズ out. I do, however, find some pictures to be amusing; I like to try and find him. That's the only thing that I enjoy about this "Slender Man".
No, of course not, I've never seen every single one of the users on this spot *cough*springley*cough* constantly mentioning him on every 質問 for the past three months. ಠ_ಠ
