Imagine you are living your normal life, then suddenly you found yourself with a weird talent and asked to fight monsters for living? That's what happened to John; one day he finds himself in a strange room and a tablet telling him about his talents, Insanity-Check and Double-Focus. And not only that, he was forced into a test to fight monsters that he only thought was a mere legend or myth.  He started to control his talent step by step, deepening his understanding of the organization that pushed him through this hell.  He was offered a choice to continue with them and enter one of the three departments of the organization: the fighting department, investigation department, or planning and technology department.  Through the story, we will experience John's journey from newbie to expert or even more.