Each generation, a competition is held to find the next empress of Honoku. The rules are simple: survive the palace's enchanted seasonal rooms. Conquer Winter, Spring, Summer, and Fall. Marry the prince. Only the yokai, supernatural monsters and spirits, are not eligible to compete. Mari has spent a lifetime training to become empress-- but she is a yokai with the ability to transform into a terrifying monster. Her fate collides with that of Taro, the prince who has no desire to inherit the imperial throne, and Akira, a half-human, half-yokai outcast. Their choices will ultimately decide the fate of Honoku.