Okay so I’ve realized that theres a lot going on with the slender man thing because our lovely website staff wrote that awesome slender man posty thing they put up. I submitted a comment and would now like to go in depth for those interested.
Slender Man is better known as Der Großmann in Germany meaning the Tall Man, He has made multiple appearances in Germany in somewhat odd and tangible forms an example of this would be Hans Baldung’s Painting where the skeletal figure, upon further examination, was found to have multiple limbs that had been painted over. Another small sliver of proof comes in the form of a poem called Schlandkwald which means “Slim Forest”. This poem mentions and describes a guardian like creature with distorted limbs that does indeed take children. While there are inconsistencies in the poem that do not match the original mythos it does bare a striking resemblance the source however lacks a date or author leaving it rather open ended with little proof as it has inconsistencies.
Looking back on most of the legends with Fairies would also suggest he is just that, a fairy. As a fairy he would be part of the unseelie court as he takes children away for their wrongdoings, based on legitimate legends from the 17th century, and punishes them until they repent/apologize to their parents for lying. To expand on the Unseelie court this covers everything from what looks like a magical mistake to our common everyday monsters. This is because Unseelie fae breed with humans or anything they see fit, this contaminates the blood line and creates those things that go bump in the night. His features are clearly a basic form of proof, more or less, that he is somewhat of a concoction of creatures with some type of magical or paranormal power. The seelie court is too pure blood minded to consider crossing breeds which is where the idea of Slender Man being Unseelie comes from. Most cases that are involving Slender Man have to do with the mysterious absence of a child, this is not uncommon for unseelie fae and therefore makes sense, an example of this would be something like Rumplestiltskin, but that is far more tame and has no mention of murder or death of the child.
He also exhibits behavior similar to that of a creature I had read about on the SCP Foundation , It is known as SCP-096. If you see a photograph of it or even gaze upon it, it will seek you out and kill you terribly and ferociously.SCP-096 is also known as “Shy Guy” if he ever turns out to exist….DO NOT SEEK HIM OUT. While not being the same as slender man the “see me and you die” aspect matches up.
While most instances require the ability to cleanly remove organs, it does not necessarily mean he has some form of medical training or access to a wealth of knowledge. He would not need to have any form of medical knowledge based on how long he’s technically been around. It could be similar to an acquired skill used to teach these disobedient children a lesson, I mean lets face it kids today are far worse than they used to be. Also another way to explain it, which is a bit cliche, is magic. Fae wouldn’t need full knowledge of the human body to cause clean yet interesting damage. Pixies would know more about it than anything as in some legends pixies are known for eating certain parts of the body. While a humanoid creature derived from a pixie might know what to remove it wouldn’t necessarily eat it.
Another theory, Slender Man is what we call a thought form or a manifestation of our negative energy or thoughts. The reason I say this is due to the fact that Slender Man has multiple names yet induces the same embodiment of fear. For arguments sake we’ll call it the fear of death as punishment. This is something that mankind has technically feared for a very long time before Slender Man was even given this specific name. With this comes the question of “Well how would that work?” Simple, Everything needs energy. As humans we radiate energy in multiple ways be it positive or negative. For anything paranormal or unearthly we are essentially walking batteries. So as along as we give in to this fear he will exist. The same thing goes for negative actions that should be punished, the person who commits the crime may not have this fear however, this does not mean that sudo justice can not manifest itself at all. Basically so long as there is evil deeds or wrongdoing Slender Man may very well exist projection of the fears and actions of mankind.
To also add on to this idea of thought form, he could also be a simple figment or our imagination pulled from one simple concept. The more people who believe in it the more power and influence the idea has thus bringing it to life. While this idea may not warrant physical action based on belief alone it could also link back to any other form of traditional methods of gaining energy much like that of ghosts. Once he gains said energy he can then become physical, but this only relates to ghosts and in that case he would not be able to kill thus suggesting that most reports are, in that case, bogus.
And so this concludes my little theory or theories rather. Hope you enjoyed reading my little rant on the mythos!
The best of Thor on Texts from Superheroes.