Levi sits in the back in his seat and look bored out of the window till he hears a new voice that he didnt knew. He looks to the teacher and sees a new gorgeous girl talking with the teacher. Levi knew instantly that this was the new girl that he needed.

Even if it means killing for her when someone nears her...

That was in levis Blood. he was a Yandere and would kill everyone that tries to near the girl he wanted.