The Bakumatsu period, a gap between the past splendour of the Shogunate era and the modern glamor of the Meiji period, is one of the most violent and intriguing places to start a romance.

Chizuru Yukimura has set off for Kyoto to find her missing father, but accidentally gets herself wrapped up in the intrigues of the Shinsengumi, a group of warriors who defends the fading powers of the shogunate.

The men in Shinsengumi are not merely fighting Emperor Meiji's forces and the strange demons, they are also hiding a terrible secret. They are hiding something among them.