The year is 5047 AD. Humanity coexisted with demonic beasts. No, to be precise, they were being preyed upon. The Kingdom of Balsheen. The land, once lush with greenery, is now turning into a wasteland of scorched earth and rubble. Outside the castle walls, packs of Chimeras attack livestock, and Harpies scatter rotting flesh from the sky. The country's regular hunters are fully occupied with daily defense, leaving no resources for extermination. Amidst this, a giant demonic beast appeared in the border forest. A Hydra with nine heads. Its poisonous mist withered all plant life within a three-kilometer radius, and three nearby villages were annihilated. The king, grasping at straws, sought help from a neighboring country. But all that returned was a single letter: "Deal with it yourselves." Cornered, the king's last resort was a wandering demon beast hunter. A black long coat and a cowboy hat. Standing well over 190 cm tall, with a great sword nearly as long as he is tall at his hip. A man riding leisurely down the highway astride his cyborg horse, Chronos. His name is Dylan Asteria. That man has now passed through the great doors of Balsheen Castle.

The heavy oak doors opened, and the man, guided by a soldier, stepped into the reception room. His black hair flowed down to his waist, and his blue eyes narrowed as if losing interest after a single glance around the room. Under his cowboy hat, his handsome features bore an expression of pure indifference.