Devin Patrick Kelley, 26, opened fire inside a Texas Church, killing at least 26 people.
The man who slaughtered more than two dozen churchgoers in Texas forced a 13-year-old girl to surrender her virginity when he was 18.
Brittany Adcock, 22, says Devin Kelley was a "monster" who forced her to pose nude for him and asked her to move into his home where she would be his "topless maid" - even after he had married.
Kelley committed the deadliest mass shooting on record in Texas when he gunned down 26 people at the First Baptist Church in Sutherland Springs on Sunday (local time). The unborn child of a pregnant woman who was among the dead.
Devin Kelley, the suspect in the shooting at First Baptist Church in Sutherland Springs, Texas. Photo / AP
Another 20 people were wounded and half of them are still in critical condition.
Two handguns belonging to the killer also were recovered.
"He was a monster," Adcock said of Kelley. "The world is a better place now [that] he is gone.
"I now know he was a paedophile. He used me to fulfill his sick kicks."
Adcock said she thinks Kelley was a "ticking time bomb" immediately after he was kicked out of the Air Force in 2012.
Kelley escaped from a mental hospital in 2012 as he faced court-martial on domestic violence charges for which he was later convicted, a police report revealed.
The report also disclosed that police who were alerted to Kelley's escape were advised that he posed a "danger to himself and others" after being "caught sneaking firearms" onto the Air Force base in New Mexico where he was stationed.
Brittany Adcock says that Texas church gunman Devin Kelley (left) was a "monster" who forced her to pose nude for him. Photo / Facebook
The person who reported the escape, according to the report, warned that Kelley, then aged 21, had been "attempting to carry out death threats against his military commanders and suffered from mental disorders".
He was apprehended at an El Paso, Texas, bus station shortly after he had run off, according to a police report filed in that city.
Kelley's troubled Air Force background has been a focus of investigators in the tiny Texas town of Sutherland Springs since he stormed into a church with a semi-automatic assault rifle and opened fire on worshipers.
Where to get help:
If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call police immediately on 111.