Chihiro-sensei (千石 千尋 Sengoku Chihiro) is the dorm teacher of Sakura Dormitory and an art teacher of Suiko. Despite being a teacher, Chihiro is lazy and only cares about drinking alcohol and trying to date men. Despite being a teacher, she often gives Sorata improper advice. She is Mashiro's cousin and is the one who arranges the transfer, but she forces Sorata to take care of Mashiro due to her laziness. She was a conscientious student of Suiko, and wanted to become a professional artist, but she changed and became an art teacher for unknown reasons instead.