Since its creation, Tougenkyou has been a place where both humans and youkai live in peace. However, following the breach of a taboo in an attempt to revive the villainous youkai Gyuumaou, the "Minus Wave" unleashes throughout the land. With this ghastly force at large, the youkai begin to lose their self-consciousness, causing them to devour the townspeople.

Tasked by the Three Aspects—the messengers of the heavens—to stop Gyuumaou's resurrection and restore peace, Sanzou Genjou rounds up three old comrades, none of which resemble the definition of ordinary. Being half-human, Gokuu Son, Hakkai Cho, and Gojou Sha are the only youkai with the power and spirituality to withstand the Minus Wave. Despite being skeptical about trusting them due to their mixed blood, Sanzou heads to the west with his companions to eradicate the growing threat.