A once-popular private school student who is now charged with brutally murdering a transgender woman went through a 'big personality shift' before the alleged slaying, an old classmate said.
Christopher Leahy, 31, allegedly stabbed trans University of Washington student Juniper Blessing, 19, more than 40 times in the laundry room of a Seattle student housing complex on Sunday night.
Seattle police said Leahy snuck into the building and allegedly attacked Blessing at random, leaving the gruesome scene for another student to walk in on moments later.
Leahy turned himself into police days after the slaying on Wednesday after surveillance pictures of the suspect were released amid an urgent manhunt.
Leahy was a student at University Prep, an elite $25,000-a-year Seattle private school, and for some time he was 'popular' among his peers, according to an old classmate speaking to the Seattle Times.
But the classmate said Leahy underwent a 'big personality shift' in tenth grade, saying there was a 'moment where the light went off a little bit where he wasn't social.'
'He went from him hanging out with us to him sitting by himself and reading books,' the classmate, who wanted to remain anonymous, said.
Leahy became 'erratic', according to his ex-peer, and said in one bizarre episode he ranted to other students about drawing 'boxes inside of boxes that made no sense.'
Christopher Leahy, 31, allegedly stabbed a transgender University of Washington student more than 40 times in the laundry room of a Seattle student housing complex on Sunday night
Juniper Blessing, 19, was found with dozens of stab wounds across her body
Leahy is facing first-degree murder charges following the murder of Blessing, who was described as a talented student with a 'gifted voice' who was studying music and philosophy at the University of Washington.
Blessing's family said the transgender student was 'courageously living their life as who they were until it was tragically cut short.'
'Juniper was simply the most amazing human being we have ever known — highly intelligent, extremely talented, and deeply sensitive to the needs of others,' her family said in a statement via the Human Rights Alliance.
But while Blessing was praised as a promising student who was looking at a career in atmospheric science, those who knew Leahy said he took a dark turn during his education.
According to court records cited by the Seattle Times, Leahy and his parents sued University Prep in 2012, alleging that the school failed to stop the bullying he faced from other students.
The lawsuit alleged that Leahy was called racist and anti-gay slurs, which forced him to take a leave of absence in his junior year 'for medical reasons related to the anxiety and stress caused by the bullying and harassment.'
The family's attorneys echoed the description from Leahy's former classmate, saying in the lawsuit that he 'went from being a socially active teenager who attended school functions, to being a withdrawn young man who became an outcast that was excluded from social circles.'
The lawsuit said Leahy was not allowed to return to the elite school for his senior year, and in 2014 the suit was settled with the family. He went on to attend a private boarding school in Ireland.
Police released surveillance footage of the suspect in the laundry room moments before Blessing was stabbed to death, and Leahy subsequently turned himself in accompanied by his parents
Blessing was doing her laundry in her University of Washington apartment complex (pictured) on Sunday night when she was brutally stabbed to death
Blessing's family said the transgender student was 'courageously living their life as who they were until it was tragically cut short'
Investigators have not offered a motive for Leahy allegedly ambushing Blessing on Sunday night.
A probable cause affidavit said officers were called to Blessing's student apartment complex around 10pm, after a fellow student said they walked in on the gruesome scene in the laundry room.
An autopsy said Blessing suffered over 40 stab wounds across her body, including to her head, neck, shoulders and arms. Her cause of death was listed as blood loss.
According to the affidavit, another female student told police that a man followed her into the apartment complex, and she hid in the laundry room to evade him.
The man then followed her inside, claiming that he was waiting for his own laundry. The woman was then able to flee into her apartment.
Police said that incident occurred just 10 minutes before Blessing's bloodied body was found in the laundry room.
Another student heading into the laundry room then said they held the door open for Leahy as he left, saying that he chillingly thanked her for opening the door as he exited the room.
That student then stumbled upon Blessing's body, and frantically called 911, police said.
Police alleged that Leahy followed another women at the University of Washington apartment complex before the alleged murder of Blessing
Surveillance cameras inside the laundry room were found to be unplugged, but police said a specialist was able to recover video in the device's memory card showing a suspect entering the room and approaching Blessing.
The suspect was seen looking directly into the camera before tampering with it, police said.
Images of the suspect were subsequently released by authorities as they launched an urgent manhunt, and two tipsters reportedly contacted police to provide Leahy's name, reports the Seattle Times.
Leahy turned himself into police on Wednesday, accompanied by his parents, and he was charged with first-degree murder on Thursday. His bail was set at $10 million, and he is next due in court on May 18.
The Daily Mail has contacted University Prep for comment.