Why yall blaming Eunwoo for being manipulated??? Chile,,, anyways so

Because he has a choice to refuse or not. He already did one time. But he still kept coming back. And this is him knowing that Hajoon has feelings for him. So he is intentionally hurting him.

Girl,,, you dont know the definition of manipulation
Professor is taking advantage of Eunwoo's feelings for him just to fuck around a bit. Maybe blame him instead