Kekkaishi - Season 1 Episode 9 Dangerous High School Teacher

A handsome teacher shows up secretly attacking students. Yoshimori is suspicious of the guy when he sees Tokine happily walking next to the guy and thinks about warning her of him being a possible dangerous player. At night, they sense an abnormality inside the school and they discover it is the teacher with three snakes wrapped around him. The teacher is actually a person with special powers but they still sense an ayakashi. It turns out that he was possessed by a parasitic ayakashi and they destroy it. The teacher is distraught that he attacked a student and is really nice by nature although he is still slightly perverted.