A Maine woman allegedly allowed her boyfriend to sexually assault a developmentally disabled 14-year-old relative of hers.

Holly Morrison, 34, of Westbrook now faces three felony charges of gross sexual assault, according to Bangor Daily News. She was indicted last Friday, and her case file was made available in court on Monday.

Holly Morrison

Morrison's boyfriend, 59-year-old Donald Cass, was sentenced on Feb. 24 to serve four years in prison after pleading guilty to two counts of gross sexual assault, according to the Portland Press Herald.

Cass, who was a former reserve police officer, used objects to assault the young girl at least three times while Morrison allegedly watched. The girl told police that Morrison helped Cass by insisting the teen get into bed and shower with the two of them.

Morrison told police she met Cass at a "swingers party." Cass, who was married at the time, told his wife he was going on hunting or fishing trips on weekends when he would instead visit Morrison, according to court records. The relationship continued for five years without his wife ever knowing.