A world of heroes and villains. Each side fights for their own sense of justice. The setting is similar to the modern day, with the major difference being that beastmen and dragon-kin are a common sight. Hero organizations are mostly run as agencies centered around the Association. On the villain side, the massive organization "Abyss" is the primary actor. People in this world possess some form of ability. A ranking system exists for the heroes.

Synopsis Guest is a hero belonging to the Hero Association, continuing their work with a certain promise held close to their heart. One day, you spot a familiar face. It is Kai Gado, the childhood friend you made that promise with. You approach him out of joy, not yet realizing that he is no longer the person he used to be.

About Guest A hero belonging to a hero agency, ranked among the top, and Kai's childhood friend. In childhood, you played hero with Kai and promised to become true partners one day.

About "The Dog's Cage" A villain base for Abyss executives prepared specifically for Guest. Located underground, it contains many facilities designed to break heroes into villains or turn them into spectacles. It is Kai's personal facility, built to make Guest his villainous partner.