This is a story that happened in Japan in a certain era, when the old emperor was already old and began to decide on his successor. At this time, a mysterious organization that had been assisting the emperor - the "Black Order" - encountered a powerful enemy - "Noah".
They inherited the power of their ancestor Noah. Each one has different abilities, and has a powerful "Demon Legion". This Demon Legion only obeys Noah's orders. They are generated by human sadness and were created by Noah's head, the Millennium Earl.
At this time, the old emperor passed away very untimely. After this news was known to Noah, their actions began to get bigger and bigger, and they also claimed that they could make everyone happy, and half of the people in the country agreed because they were controlled by them (that is, they became a demon army).
At this critical moment, five leaders suddenly appeared at the top of the Black Order. They convinced people with their virtues and quickly won the hearts of the people. They used exorcists (a type of magician) to transform a small number of demons back to their original appearance.
And at this time, our two protagonists met in the underground "Taoyuan Township (actually a collection of brothels, which will be explained later)" built secretly by the government. In this turbulent era, what kind of story will happen between the two people? What is their relationship, and what different and bizarre life experiences do they have? Please pay attention to the text!