What if

I haven't seen anyone mention it but could it be that he's not just a masochist but is actually sick? As in being hit/in physical pain doesn't only satisfy him sexually but also kinda numbs existing pain within him or other symptoms he has. I know people who hit their head when they have a headache (please don't do that). What was strange to me is that he seemed to be at peace and woke up refreshed when Incheol knocked him out cold, like who would feel good after that? So I think there's a serious underlying issue with him and I believe he got addicted to getting beaten up since it's the only thing that alleviates it, and the only thing he knows to do to stay numb. Could be the other end of spectrum and he can't feel anything, so he resorts to that to feel something? Also a possibily. Maybe I'm just reading too much into it, but to me it feels like there is way more to unpack since it's soothing for him almost not just a kink or a turn on..