Crimson Hero (紅色HERO, Beni-iro Hīrō) is a manga series written and illustrated by Mitsuba Takanashi. It was serialized in Bessatsu Margaret.
The series follows Nobara Sumiyoshi, a 15-year-old tomboy with a passion for volleyball. Her love of the sport is disapproved by her mother who wishes Nobara to become the next hostess for the ryotei (old-fashioned Japanese restaurant) run by the family. Frustrated by her mother's constant pressure and frequent comparisons between herself and her sister, Nobara finally decides one day to move out and make it on her own. After seeking out her aunt for help, Nobara ends up living with four members of Crimson Field High School's boys' volleyball team as their dorm mother. What follows is a drama of a girl's dream of making it into volleyball, and her difficult journey in fulfilling that dream.