here is my hypothesis its a pretty good one actually i figured out the slender man is a guy in a morphsuit but that has nothing to do with this the people had to make a movie or something for college so they went to make a movie called marblehornets but then they decided to make a horror movie i had to do something similar to this i had to make a video and post it to youtube but in there case they made the video and kept going alot of college people like to fuck around one of them had a morphsuit and said hey dude lets use this as the monster