Kyoukasho wa Oshiete Kurenai

A high school girl's ghost, Yuuri, follows her boyfriend's younger brother for unknown reasons. Shino tries to deter Takeomi by saying she won't engage in any physical contact until marriage, but he agrees, and they remain close until Shino's first boyfriend arrives and exposes her true motives. Hinokawa is interested in learning about love beyond what is taught in school, but the teacher she is drawn to does not respond as she hopes.