In 2048, endless heavy rain began to fall all over the world.
In order to survive, humans have built floating fortresses on the plateau.
Along with the heavy rain came a series of strange events.
Human beings unexpectedly discovered that they could overdraw their lives and body functions in exchange for the power to control evil ghosts.
The ghost masters who obtained the power of the ghosts started a battle with the ghosts.
200 Years later, the heavy rain that lasted for hundreds of years quietly stopped.
Countless invincible ghosts in the underwater city have revived and tried to devour the world.
