The first stage adaptation of the "Togabito no Kokuin" light novels. A dark fantasy romance between a vampire and Jack the Ripper.

The first play in the series. After the third world war, advances in genetic engineering have led to the creation of TRANS, a technology that allows people to freely choose their gender. However, some people who have undergone this procedure have gained various abilities beyond human comprehension. We call these people Heli-X.

The second stage adaptation of the "Togabito no Kokuin" light novels. Unlike the first show, the story goes beyond the original novels introducing characters who are unique to the stage version.