The end of the 19th century. A vampire's wife is murdered, and the detective known as the "cage user" is called in to solve the crime. But there's more to the detective and the curtained birdcage he carries...

Class troublemaker Ryu Yamada is already having a bad day when he stumbles down a staircase along with star student Urara Shiraishi. When he wakes up, he realizes they have switched bodies and that Ryu has the...