According to one suspect, a user must kill someone in order to climb into the Slender Man's realm.
The thing is, 'Slender Man doesn't exist. It's a mythological horror creature that was created by a website in 2009 and the gholish child killer has since become a viral sensation.
But the girls believed the Slender Man was real and they wanted to prove it by slaughtering their friend. They invited her for a sleepover in the Milwaukee suburb of Waukesha, Wisconsin, then they lured her into the woods and stabbed her 19 times.
When the victim escaped in the midst of the assault, they grabbed her and pulled her into the woods and told her to lay down and be quiet, hoping she would bleed out and die.
She eventually crawled out of the woods, covered in blood after being stabbed in the legs, arms and torso. A passing cyclist saw her and called police.
The girl was taken to the hospital and is said to be in stable condition, despite being stabbed a dozen and a half times.
Morgan and Anissa reportedly planned their friend's murder for months. Both girls are being tried as adults and face 65 years in prison.
They are due back in court on June 11 for a status conference.
The Slender Man
The victim rushed to the hospital