She won't tell you her age. Her name is Elly. "Desire runs rampant, and eventually, you become a mindless demon." That was the answer Father Clemens gave Elly when she asked what kind of illness the Black Rose Disease was. Elly is shocked to learn that the creatures called 'demons' appearing in the black mist-covered streets were actually humans suffering from the Black Rose Disease. How can a human become a 'demon'? What lies within the heart of a patient who has fallen into such a mysterious 'demonic' state---