I felt this on a spiritual level
I would recommend re-reading it as it will change your perspective, MC forgot hypnosis part but he remembers wild dreams, hard-ons, jerking off to his brother and all this culminated when he was horny and woojin was able to convince him he can help him. I also think that deep down mc feels attracted to woojin his issue is that he didn't want to be older brother living in a shadow of more capable person in comparison, his true self is a little baby, he wants to be pampered and held not losing attention of his mother and being isolated due to circumstances outside his understanding
Ooooooor he got straight up manipulated and got Stockholm syndrome of some sort or something ╮(￣▽￣)╭
sorry, ik why woojin is so casual abt them fking, but how come the MC is so blasé too?? thats his brother! sworn enemy no less. has the hypnosis really dulled his sense of decency to such an extent? how sick. i still wanna keep reading tho, lmfao. i need therapy.