Boku to 4-nin no Onna Kyoushi

Shun is a high school student. He has a regular head but looks weak and he is prissy. That is why he is sometimes teased by other students. However, he is living a peaceful life at school. But his peaceful life is destroyed by a new teacher Kasumi, beautiful and pure. He gets stiff when she is around and can't move even his tongue. When he knows Kasumi is engaged to Yoshio who is the worst teacher at school, the story starts to ....