How did Slender Man go from fiction to fact?

Like all 12-year-olds, Morgan and Anissa fantasised about their favourite fictional characters. The only distinct difference was that they were obsessed with villains in popular culture and supernatural evils in internet fiction.

Morgan, in particular, affectionately called Voldemort from J.K. Rowling's Harry Potter series, “Voldie,” as if he were a pet.

The pair, whose friendship blossomed on the ride to and from school, had a shared a fondness for Slender Man among other mythical characters. Just two months before the stabbing, Morgan's father Matt posted a drawing Morgan made of Slender Man: “Only Mogo draws Slender Man in crayon on a napkin when we are out to dinner”.

It's unclear when the internet villain transcended from fantasy to reality for the girls, but it certainly became a preoccupation of theirs. Police found maps and checklists referring to the stabbing and days before the incident Anissa wrote a will, bequeathing all her possessions to her parents, as well as an adieu: “This is my final wish to those who care, do not grieve my absence, but remember me for who I was. I love and cherish you all and wouldn’t do you harm,” New York Magazine reports.

“We were probably going to be spending the rest of our lives [with Slender],” Anissa, later told police, “and I didn’t want to forget my family.”

Morgan told police that it was “difficult” to not tell anyone about their plotting and that she went through with the stabbing in part because “I didn’t want to make Anissa mad. It’s hard enough to make friends. I don’t want to lose someone over something like this.”

What happened after the stabbing?

For the last 14-months Anissa and Morgan have been living in a juvenile-detention facility in Washington County. They are intentionally kept apart, living in separate living quarters, attending separate classrooms.

An effort to have them trialed as children failed in August 2015, after the judge cited the particularly vicious nature of the crime and ruled to maintain their status as adults. Psychologists agree that by the age of eight, and certainly by 12, most children are as able as adults to sort out what’s real from what is not.

During police questioning on the day of the stabbing, Anissa admitted that the Slender Man “does not exist. He is a work of fiction.”

Morgan, however, who suffers from schizophrenia - a brain disorder that causes people to abnormally interpret reality - had a greater attachment to the fabricated tale. But she too admitted in her interview that the attack on Sally was “probably wrong. I honestly don’t know why we did this.”

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