Black School Rules.

Sōra is a 2nd-grade high school student, but he is virtually invisible at school. He is friends with Chūya. Chūya's personality is completely different from Sōra. Chūya does unpredictable things and that surprises those around him. Sōra and Chūya both have feelings for the same girl at their school. The girl refuses to attend school, because she doesn't want to change her brown hair to black. Their school has unreasonable rules, including requiring all students to have black hair. For the girl that Sōra and Chūya like, they stand up to change their school's black school rules.