Utou Chizuru

Shuuichi's younger sister who attends a private all-girls school, she is a honor student who is loved by all the teachers.
When she was young she used to be sickly. Though she is fine now, even till this day she fondly remembers all the time she spent with her brother back then.
To further her forbidden relationship with her brother Chizuru sometimes approaches him without restraint. Other times she is a little embarrassed to do it alone, so she cooperates with her cousin Suwana.