What is the teacher's purpose in the story?

That's a good question homie, that's a good question

What kinda question is that?? He’s literally the MC of the story. Hes single handedly carrying the story rn.

i think there's something deeper that has yet to be revealed from teacher side, we can see how his memory is jumbled. my theory is actually it might have been him that kill his own father. you see how he had the episode to take knife and stab himself so yeah

and if you remember how Guwon said that "he and the teacher are similar" (in context of violent tendency, probably) because I think Guwon might have witness teach unkonwingly killing his father