Responses
Yeah I don't really get it. The professor wasn't really even that interesting of a character; he was just a skinny-eyed man with a whip. His is a bit mysterious but I think people are just justifying his relationship is the side story because his relationship fulfills many people's "seme to uke" kink.
I thinks it’s funny how you guys hate on Eunwoos and Hajoons relationship, but praise the Professors relationship he has with that man even though you can clearly see how toxic and manipulative he is towards the Professor.