Yup and to fix his childhood friend/love of his who's suffering because of the blonde dude. Our mc he'll have to do the same to her as to what she's doing to the current girl because she's breaking down as time goes by because of the blonde dude being used as a toy, so he'll have to go through the lustful means of rehabilitating her with his contracted demoness's help similar to this girl to mend the relationship between them.

Revenge was never the goal. Rookie mistake. The author is out to write fallen characters having sex under extremely eccentric circumstances. The whole cat & mouse game is just background dressing.

You can barely call it NTR, because across the board, you've gotten hold of next to nothing to any NTR victim. Not the MC when the bullies raped his childhood crush, and not the bullies over the course of these chapters of the girls being tortured into Stockholm states of mind. We don't care about those guys, we just enjoy watching the women fall.

The "pleasure of torturing" is the revenge!
That was the whole point of the demon stopping MC from merely stabbing the rapist.