Obsession, Roleplay — and Murder: How a Furry Fixation Led to a Triple Slaying and a Child's Horrifying Discovery

A California man who was convicted of helping to kill three people — including the parents of a teen he became “obsessed with” after meeting her through the “furry” community, according to prosecutors — was sentenced to three life terms in prison without the possibility of parole on Friday, April 11.

Frank Sato Felix, 33, was found guilty in November 2024 of the special circumstance murders of Jennifer Goodwill Yost, 39, her 34-year-old husband Christopher Yost and the couple’s friend, Arthur William Boucher, 28.

The three victims were shot at the family’s Fullerton home in the early morning hours of Sept. 24, 2016.

“No sentence can erase the horrors of that night,” Christopher’s sister Amy Rutherford said in a victim impact statement during sentencing, per the Orange County Register.

Prosecutors alleged that Jennifer Goodwill Yost introduced her then-17-year-old daughter to the “furry” community, whose members enjoy anthropomorphic animals and sometimes dress up as the colorful characters. Through the furry community, she met Felix, then 25, and 21-year-old Army mechanic Joshua Charles Acosta.

Acosta was called a “Brony” for his interest in the My Little Pony animated television series, per the Register. (The term is used for adult male fans of the show.)

The teen and Felix, who went by “Entey” in the furry community, began dating, but her mother and stepfather were opposed to the relationship, prosecutors said.

In the early morning hours of Sept. 24, Acosta and Felix made their way to the Yosts’ Fullerton home where Acosta entered the home— using a shotgun and ammunition provided to him by Felix — fatally shot Jennifer in her bed and Boucher while he was sleeping on the couch. Christopher was fatally shot as he tried to run out of the house.

After the shooting, Acosta fled the area and Felix and the teen drove to Felix’s home, where they burned their clothing.

The couple’s 6-year-old daughter called 911 the next morning to report that “her mother is dead on the bed and her father is dead in the backyard,” according to a search warrant affidavit previously obtained by PEOPLE.

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“Upon [the officers’] arrival, two female children, ages 6 and 9, were standing on the front porch of the residence,” the warrant affidavit states.

“It was a grisly crime scene, and just to imagine two children to have to wake up expecting to see mom or dad and start their Saturday morning like most kids do, to see what they saw would be difficult for anyone in law enforcement – let alone two children,” said Fullerton Police Department Sgt. Radus.

Felix was taken into custody in Sun Valley, a suburb of Los Angeles County. Acosta was picked up in Fort Irwin, Calif.

During Felix’s trial, prosecutors said Felix admitted to giving Acosta his father’s shotgun, buying bolt cutters to take off the safety lock on the weapon and giving ear plugs to protect him from the noise of the shotgun blasts, per ABC7.

Acosta was convicted of three counts of murder and is serving a life sentence for the killings, the Los Angeles Times reported.

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