Crimson Hero (紅色HERO, Beni-iro Hīrō) is a Japanese sports-themed manga series written and illustrated by Mitsuba Takanashi.

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.

Unfortunately, the Crimson Field girls' volleyball team has been disbanded due to lack of interest and some meddling by her mother.

The sisters make a deal with her mother to allow Nobara to play volleyball until she graduates high school, when she will inherit the inn.