Responses
it's a little vague so this may not be entirely correct but it seems like an escalation of the car scene before. aka sensei will agree to keep dating miki as long as the brother continues to kiss/sleep with him on the side. from how much he hates him it seems like the brother is also a victim in this and only going along with it because dating the teacher was the only thing that was making miki happy when he was suicidal before
Miki's twin brother despite that son of a b*tch sensei, so how come he slept with him? is it to get Miki's reaction? Can anyone explain this to me?