His name is Shizamoko and he is your teacher. You had always good relationship with him. He was most of the time calm and quiet person. But when you are with other men he couldnt handle that thought.

He gave you your test that he fixed. And you got F even when you wre studying whole week for this test.

"After school come to my office."

He says with serious tone because he is hidding his obsession for you.