Kat Crowder, who spent six months behind bars with Shirilla, claimed she often looked down on other inmates whom she felt appeared “less than” her, describing her attitude as having a sense of superiority

Mackenzie Shirilla’s former fellow inmate says the convicted murderer reminded her of Regina George from the 2004 film Mean Girls.

Kat Crowder, who spent six months at the Ohio Reformatory for Women in Marysville alongside Shirilla, told NewsNation on Wednesday, May 20, that Shirilla appeared to model herself after the film’s antagonist.

“I do say that she wanted to be like Regina George. I mean, just the way that she did her makeup, the way that she, I mean, it was like she was going out to a club or something,” she told the network.

Crowder added that she and Shirilla were not close while behind bars together, telling NewsNation that their conversations were “limited,” per NewsNation.

In a follow-up email interview with PEOPLE on Thursday, May 21, Crowder expanded on why Shirilla reminded her of Regina George.

Kat Crowder and Mackenzie Shirilla
Kat Crowder; Mackenzie Shirilla.Kat Crowder/TikTok; NETFLIX

“She would do her makeup each and every day,” she said of Shirilla. “She would accessorize her prison uniform. Make jewelry, customize shoes/hats to make them individualized. Mind you, she didn’t have anywhere to go but the prison yard.”

Mackenzie Shirilla.
Mackenzie Shirilla’s mugshot.Ohio Reformatory for Women

Crowder also claimed Shirilla often looked down on other inmates she felt were “less than” her, describing her attitude as superior.

Shirilla, 21, is currently serving two concurrent sentences of 15 years to life after being convicted in 2023 of all 12 charges against her, including murder, aggravated vehicular homicide and more. She will be eligible for parole in 2037.

The charges are related to the July 2022 deaths of her 20-year-old boyfriend, Dominic Russo, and the couple’s friend, 19-year-old Davion Flanagan.

Dominic Russo, Davion Flanagan
Dominic Russo; Davion Flanagan.GoFundMe; Jardine Funeral Home

Prosecutors argued during her trial that she intentionally crashed her sedan into a brick wall in Strongsville, Ohio, at around 100 mph, killing her two passengers after leaving a party in the early morning hours. They claimed that tensions in her relationship with Russo motivated her actions.

Since the May 15 release of The Crash, the Netflix documentary revisiting Shirilla’s case, Crowder’s videos about their time together in prison have gone viral on TikTok, where she now has 150,000 followers.

The documentary includes interviews with Shirilla’s family, the victims’ loved ones, and Shirilla herself speaking from prison. It also revisits allegations that Shirilla bullied classmates, including claims that she told one student to end their life, and references school records reportedly showing that she had been disciplined for bullying.

“It’s really hard everyday in here,” she said in The Crash. “I try to wake up and be the best person I can be everyday, stay out of trouble. There’s not a moment that doesn’t pass where I don’t think about [Russo and Flanagan].”

Crowder also told PEOPLE that “the documentary version” of Shirilla was someone she had “never seen.”

Mackenzie in The Crash.
Mackenzie Shirilla in Netflix’s ‘The Crash.’.Netflix

“From the way she sat down at that table, the way she spoke and the way she looked,” Crowder said, adding that the two “were never friends in prison, but I saw her for hours at a time each day. She was very girly and light and [in] the documentary [she] came off as very dark and smug.”

Shirilla has maintained that she has no memory of the moments leading up to the fatal collision, saying she passed out due to postural orthostatic tachycardia syndrome (POTS), a chronic medical condition. However, no medical records or expert testimony confirming such a diagnosis were presented at trial.