Nearly seven months after a former West High School teacher was killed during what her boyfriend described as “aggressive sex,” he has been charged with her murder.

Nathan Edward Parry, 34, was charged Friday in 3rd District Court with murder, a first-degree felony, and obstructing justice, a second-degree felony. A $1 million warrant for his arrest was issued.

According to the charging document, Parry called 911 on Oct. 21 to report that “he believed his girlfriend” — Rebecca “Becky” Michelle Sullivan, 41 — was dead. Police arrived at Parry’s home at 734 Park Street and found Sullivan “in full cardiac arrest.” She had a “large, v-shaped laceration on her forehead and visible strangulation marks on her neck.”

Sullivan, a Salt Lake City native, taught French at West High during the 2017-18 school year. She was pronounced dead at a hospital, and a doctor told police her injuries “did not appear consistent” with Parry’s version of events.

According to court documents, Parry told police he and Sullivan had fought at a party and he went home. She later joined him there and, according to Parry, “they started to have sex, placed restraints around their necks, and they both began to lose consciousness.” He said he awoke to find Sullivan unresponsive, and told police, “I hope she is OK.... This is what happens when you have aggressive sex.”

When told of Sullivan’s death, Parry told police he and Sullivan “were trying to commit suicide together.”

When he was interviewed later by police, on Nov. 9, Parry told detectives that on Oct. 21, he returned home from a bar without Sullivan; he took a Benadryl; continued to drink; and fell asleep. He said he “awoke to find Sullivan standing over him” and “the next thing he remembered was that they were hanging together from the stairs in one single, webbed strap.” He told police he was able to “grab a pair of scissors from … the top of a nearby set of drawers and cut them down.”

According to police, the carabiner from which Parry said he and Sullivan were hanging was 5 feet and 2 inches off the floor — Parry is 5 foot 10 and Sullivan was 5 foot 6. The detective also noted that the set of drawers from which Parry said he retrieved the scissors “was over 9 feet away from the carabiner strap,” adding that “Parry’s multiple explanations were inconsistent with the evidence and with the reconstruction.”