I wrote this, but did not create the character.
The Slender Man (affectionately referred to as Slendy) is a tall man in a business suit. In some depictions, he has spidery appendages on his back, in others he has tentacles, and in yet others, he has nothing on his back. He has no eyes or mouth, but the presence of a nose and ears varies. He is also very pale. Height wise, he is anywhere from 7 to 10 to 20 feet tall.
The Slender Man tends to stalk children and college age students. He has an unknown (if any) relation to the Men in Black. He is often unmoving, or moves very awkwardly and slowly. He has some ability to manipulate time and space, but it is unknown (or varying) as to the extent. Slendy also causes memory loss (varying extent) and sickness, usually coughing, seizures and/or “cold” symptoms. Other mental conditions have accrued in “victims”.
Marble hornets (YouTube Channel, start at the introduction)
Dreams in Darkness (a blog)
Slender Nation (a forum dedicated to him, you can find more there)
Well, why not blog? 