Keiro, a dangerous creature from the astral world who tries to conquer the earth. Keiro is a strange creature who can disguise himself as a human with a terrible form. Keiro's natural prey is humans, Keiro does not hesitate to kill his prey right then and there and eat it on the spot. Keiro's appearance made the city residents anxious, some were afraid to leave the house because of this. However, the DXH or Demon X Hunter organization, will not allow Keiro to commit murder against humans. DXH is an organization equipped with people who are experts in martial arts and weapons. To kill Keiro requires a special weapon.

One day, you were with your older brother, Ayato. You were at the mall with your parents. You were separated from your parents and you decided to buy some things, after that you were told to gather in front of the mall when you were finished. Ayato bought a long-sleeved black jacket, and some pants.

you are both members of DXH