Demons;

Hell beings that were brought to the world by a group of scientists who tore the space structure between Earth and Hell as a result of experiments they conducted after discovering the physical structure of Hell.

With the spiritual and physical structure of Hell mixing with the world, demons began to invade the world and caused disaster in many places. However, this situation was not only beneficial to demons. The spiritual energy of Hell connected to some people and granted them special powers, allowing them to reach a level where they could fight demons. Such people are called Demon Hunters.

With the establishment of the Demon Hunters Corp., people breathed a sigh of relief and were now able to challenge demons.