Year 2055, 4 years after the events in Danball Senki W. LBXs have become the world's largest hobby, big enough for pro leagues to be established, and people to make their entire living off being an LBX player. 14-year-old Arata is a new transfer student at Kamui Daimon Integrated Academy on Kamui Island, near Japan. Known to be the most prestigious institution in the world for raising LBX players and mechanics, entrance to the academy requires an extremely competitive hurdle of being the champion of at least 3 official tournaments. Along with other members of his platoon, they face rivals and delve into the secrets lurking within the academy.

At the end of the 20th Century, the world is facing destruction from massive earthquakes, bad weather and other abnormal phenomena. In Tokyo, Setsuna Kai, a young boy who lost his mother when he was very small, practices Kendo every day because his goal in life is to become strong. As always, his rival Mirai Kaname defeats him and Setsuna feels sad. On his way home, a messenger from the Devil's World appears before him. This messenger proclaims that the various abnormal changes in the world are the work of the Devil. The world will come to an end unless the Devil is conquered. The only ones who can save the world are the "Devil Children." Thus begins Setsuna's adventure in the Devil's World. From RebelliousArt: A boy develops powers to save the world from monsters. He joins up with others who have similar powers to him.