In the human town of Zetsuya, Makoto and company meet a girl named Rinon who is searching for her missing sister. That night, they`re attacked at the inn. They learn Rinon`s sister Toa is being held captive because of her debt. As Makoto nearly loses his cool for certain reasons, Tomoe and Mio go to rescue Toa instead. However, a single man stands in their way.