He's not drunk right?

I think its just how he likes it.

I can relate lol

Prof doesn't care about gender...uhm, you could say he is treating him roughly to actually hurt him physically since garam said he could endure all the pain inflicted on him. He is just showing garam that blade like him will always know how to hurt others.

But he can be tender too right? He was biting him and when Garam said it hurt, he started licking the same wound he caused. But I did notice when Garam told him he was gentle, he started being more aggressive with him.

He can be tender...but just not now- it feels like a spoiler but I will just say that he only became tender when he stopped thinking of himself as a blade. Garam will get used to his roughness and even to his sadism. But I mean, I know what people will say after they read the later on chapters that- "uhm, garam likes it rough and is a pervert" but no, garam always wished heejae to be gentle. But heejae never gave him that. So garam started convincing himself that he loved the pain- that the rough touch from his prof was the most certain and intense affection he could get from him... It's sad actually.

Now I'm sad but yeah, Garam seems like such a romantic. All his thoughts, since the beginning, were leaning to affection and soft intimacy so knowing he convinced himself of the contrary because that was what he was receiving from the professor as a form of validation of his feelings or something, it's so depressing... But glad to know someday that would change... I do love the progression of the story and how the characters mutate. It feels natural.