Did he even molest them?

Some people were sure it was implied they were molested, others didn't think so. I'm not so sure myself, it was quite vague. I think he probably got off mostly on just keeping them captive, knowing they were terrified of not knowing what he was going to do to them, threatening them, beating them, feeding off their fear and eventually killing them. That's how I saw it but others might see it differently.

Well this was a Stranger Things" type movie made for kids to young adults.. So there wasn't going to be any actual depictions of sexual assaults on screen.. Often times sick people like the killer are also sadists and they don't necessarily get any sexual pleasure from penetration, but rather from torturing their victims and that is what the killer was doing for certain.. The beatings that he gave the children with his belt was an obvious indication of this..

I was really glad not to see it depicted in any way. I just don't want it in my brain, what he did was bad enough for the film.

Maybe I missed something but I didn't think he was molesting them. I think he was bullied and abused when he was young by boys the same age as the ones he took and killed them for the revenge and pleasure of being able to take down "defenseless" boys.