The story takes place in the world of "Earth Dash", an alternate version of Earth where human society is far more advanced on the moon than on the planet's surface. A popular sport is BFB (Big Foot Basketball), where players ride mecha called "Big Foot" in a giant basketball arena, playing basketball. In the city of Rolling Town, Dan JD and his companions took the sport to the streets, which was renamed "Basquash", and they embark on a journey to overcome their hardships of the past and make their dreams come true.

"To live, we formed a pact." On the day the Xianglong (Shanron or Soaring Dragon) Crisis occurred in 2031, Leon Lau was right in the middle of the unfolding events. The Quantum Reactor, a next generation energy device developed to replace dwindling environmental resources, exploded and unleashed an unknown energy. As a result, the global environment changed overnight. Living things (besides humans) and machines each underwent their own unique evolution, and the B.R.A.I. (Biological Revolutionary of Accelerated Intelligence) entities in particular evolved and came into being. Because of them, humanity was driven to the brink of extinction. Humans fight the B.R.A.I with M.O.E.V. (Multi-purpose Organic Evolution Vehicle) variable units. Seven years after the Xianglong Crisis, Leon is in the wilderness on the edge of the "absolute defense city" Neo Xianglong. Living with Chloe Lau under a "family pact," he conducts his own research to counter the B.R.A.I. The awkward Leon and the busybody Chloe. They live day-by-day as if to forget the past for the moment. However, threats unrelentingly draw near. [ANN]

Pairings: Kanda x Allen, Allen x Kanda