Throughout history, humans have been at enmity with Beastmen, a race capable of shifting shape owing to their genetic "Beast Factor," and Beastmen have been pushed into hiding as a result of this battle. Anima City provides a secure place for these persecuted people to live their lives free of human intrusion. During a festival commemorating the town's tenth anniversary, Michiru Kagemori, a human who was unexpectedly transformed into a tanuki, discovers that Anima City is far from paradise. Shirou Ogami, a virtually invincible wolf and sworn guardian of all Beastmen, confronts her when she witnesses an explosion in the square. As they chase the perpetrators of the attack, the two find that Michiru is no ordinary Beastman, and they set out to uncover her enigmatic background and present.