Anastasia, a former inmate at the Ohio Reformatory for Women, made the claims in an interview with Daily Mail last week.

Shirilla was the only survivor in the car wreck where her boyfriend, Dominic Russo had been a passenger, alongside his friend, 19-year-old Davion Flanagan, in a car being driven by then 17-year-old Shirilla.

Russo and Flanagan were killed instantly when the 2018 Toyota Camry rammed into the side of a brick building in the town of Strongsville, Ohio.

Russo, 20, sent a heartbreaking final text to his father moments before the collision. Picture: Netflix

In a new interview, one of her former fellow inmates has claimed that she was left “deeply disturbed” by her time behind bars with the murderer.

“She said she was suicidal, but she almost looked as though she was enjoying (telling the story) – like she was amused by it,” said former inmate Anastasia, who didn’t supply her last name.

The ex-inmate said Shirilla was a heavy user of prison drug K2, which is made from smoking paper sprayed with chemicals.

“She said the devil made her do it,” Anastasia recalled. “She said the devil was pressing on her foot… She wanted to make it sound like she was a little devil girl, and that this is what she intended to do. Like there was a reason that Dom had to die.”

The new documentary documenting her case — The Crash — quickly climbed to number 1 on Netflix’s most popular list since it was released earlier this month.

Shirilla appears in the documentary from behind bars — where she claims to feel remorse for the fatal crash and insists she’s “not a monster”.

In the days leading up to her arrest, Mackenzie mourned alongside her community for the two lives she took.

She was arrested three months later and found guilty of all 12 charges brought against her in 2023, including murder and aggravated vehicular homicide. Picture: Netflix

While healing from brutal injuries and being supported by her dead boyfriend’s family, she posted obituaries online

“You had such a perfect life ahead of you,” she captioned one photo.

“I miss your laugh, your perfect smile. I feel your energy around me everyday i just wish it was physical. God u are the last person to deserve this. You had such a perfect life ahead of you… I wish I told you all this more. Please wait for me.”

It painted the picture of a loving young couple, however in reality the pair struggled after they moved in with one another, with the relationship turning volatile.

Friends of the couple told police that Mackenzie was “disrespectful” and often threatened to break up with her boyfriend, accusing him of cheating on her and having “poor communication skills.”

She was arrested three months later and found guilty of all 12 charges brought against her in 2023, including murder and aggravated vehicular homicide.