BBM. While the second statement I agree with, the third one, that he will not kill again, I disagree.
About "a god-fearing person with a conscience" - don't buy it!
He may be religious. He does not understand what morality is. He had sadistic, sexualized dreams, maybe for years, and now he acted on them.
He is probably way less mature than his biological age. Probably a teenager in an adult body, and lots of these questions are the norm for teenagers.
This very phrase - BBM - is in total contradiction with your previous statement about a "god-fearing person" who would not kill again.. What you are discussing are torture instruments, meaning, sadistic premeditation.
He would kill again...unless stopped. And he would hunt for someone not able to resist. A child, a disabled person, a small-frame woman.
Bingo! This is exactly what I thought he said. Or something very similar. Or, "Guys, this bridge is unsafe for walking and is to be closed. Down the hill". Something that would make them feel guilty and ashamed.
The rest is nothing new, sorry...
I also have the feeling that he was daydreaming about a sadistic, erotic, encounter, for many years. Maybe since high-Middle school. What people in the town he used to live in might remember would be some anonymous letters mentioning some torture elements ("a rope. A lighter. A knife" - just as an example). Or possibly, he shared these dreams with peers. Anyhow, people wrote it off as part of him being "odd", but they may remember it now.