Hase Saeko

Hiroshi's older sister and a teacher at the Inamura Academy. In the professional capacity she acts like a serious and responsible person, but she's actually a spoiled sister who always relies on her brother. Saeko's a huge brocon who loves Hiroshi and wants to be with him forever, she gets jealous very easily and doesn't accept Hiroshi having a girlfriend.

She can become quite scary and feared even by the delinquents. Sometimes she acts in a cruel manner and used to bully other children when she was a kid, especially Hiroshi.