'Slender Man' Girls Plead Not Guilty They face decades in prison over attack on classmate By Newser Editors and Wire Services Posted Aug 21, 2015 12:21 PM CDT 16 comments Comments One of the two accused girls, in a file photo from court. (AP Photo/Waukesha Freeman, Charles Auer, Pool) (Newser) – Two 13-year-old Wisconsin girls accused of luring their friend into the woods to repeatedly stab her as a sacrifice to the fictitious Slender Man character pleaded not guilty today. The teens from the Milwaukee suburb of Waukesha are being tried as adults and face decades in prison if they are convicted in the 2014 attack. A judge entered not guilty pleas on behalf of both girls at a brief arraignment hearing. The girls did not speak today, notes the Milwaukee Journal Sentinel. Their victim somehow survived the attack, and each faces a charge of attempted first-degree intentional homicide. Investigators have said the two plotted for months to lure their friend Payton Leutner into the woods after a sleepover. They intended to kill her, police say, to win the favor of Slender Man, described as an unnaturally tall and thin man who wears a dark suit and has no visible facial features. Slender Man stories have proliferated online in recent years. They wanted to kill for him, in part, to prove his existence, police documents allege. The girls, 12 at the time of the stabbing, believed they would have a home in Slender Man's mansion if they carried out the attack, police say.