Hina moves back to her old home town only to find that the high school is run by two opposing factions, and students identify themselves based on the color of their school uniforms: Black for the followers of the ostentatious, violent Nishizaki, and white for the followers of the misanthropic, clean-freak Isshiki. And, as if it wasn't complicated enough, there are the "grays," who wear their own clothing, deciding to be their own people. Hina finds herself stuck between the leaders of the two factions, and it seems to be turning violent.