LOS ANGELES — A Sun Valley man was convicted Tuesday for his role in the killings of the mother and stepfather of a 17-year-old girl whom he met through the "furry" subculture, officials said.

Frank Sato Felix was 25 years old when he and then-21-year-old Joshua Charles Acosta, an Army mechanic, met the girl. The subculture includes "furries," or people who dress up in elaborate animal costumes.

Felix and the teen began a romantic relationship, prosecutors said, but her parents, 39-year-old Jennifer Goodwill-Yost and 35-year-old Christopher Yost, disapproved of it.

On Sept. 24, 2016, Felix and Acosta drove to the Yosts' Fullerton home, where they planned to take the 17-year-old and keep her away from her family until she turned 18.

The teenager left her home and went to Felix, who was waiting in a truck outside while her family slept. That's when Acosta, armed with a shotgun, walked into the home.

Acosta shot 28-year-old Arthur "Billy" Boucher, a family friend who was asleep on a sofa in the living room. Acosta then walked into the master bedroom and shot Goodwill-Yost.

Yost tried to escape to the house patio, but was shot in the head.

Felix provided the shotgun and ammunition.

The couple's 6- and 9-year-old daughters were left alive in the house. They discovered their parents' bodies in the morning and called 911.

During Acosta's trial, the 17-year-old testified that her stepfather had repeatedly molested her between the ages of 7 and 15, according to the Orange County Register. She also testified that Felix had "blackmailed" her to have sex with him, or he would tell her mother about the abuse.

She'd planned to tell her mother and run away from home the day of the killings, she said in court.

Acosta's attorney noted during that trial that the teenage girl had lied to police and prosecutors, including alleging that her mother had abused her and had previously denied telling anyone about the alleged abuse.

On Tuesday, Felix was convicted of three counts of special circumstances murder.

In 2018, Acosta was sentenced to life in prison without the possibility of parole for the killings.

"Two little girls, 6 and 9, went to sleep not knowing the last time they would see their parents would be when they woke up to find them shot to death," said Todd Spitzer, Orange County district attorney. "Violence is never the answer, and a sick and twisted plan turned into life behind bars for two young men."

Felix, now 33, is set to be sentenced Jan. 17 at the Central Justice Center in Santa Ana.

©2024 Los Angeles Times. Visit at latimes.com. Distributed by Tribune Content Agency, LLC.