Akai, a high school student in modern Japan, one day split into two bodies and personalities, Akaraimaru and Shirousamaru, and went back in time. The two appear in a science fiction future where the Cat Tribe Liberation League and the central human government are at odds with each other. The radical Akaraimaru becomes the symbol of the cat tribe, while Shiranaimaru, with his strong logic, cooperates with the cat tribe and leads them. When Akai's classmate Shoko, who is in love with Akai and has been aggressively pursuing him, joins the fray, the intentions of both sides become intertwined...then Paradox, a tribe ruled by dogs, joins the fray, and the battle becomes more fierce than ever. Which way will the battle for the future of humans, cats, and dogs turn?