Ibuki Mei♀

Mei is the protagonist's teacher. She is a graduate of Eiden Academy and in her mid-20's. She attracts boys, including the protagonist, with her mature charm, which is sometimes used to control them. Although unusual at an all girls school, she is very popular among the female students. The girls respect and look up to her, often coming to her for advice. When she drinks, her personality changes and she starts bawling.

[From MangaGamer]