Hibaru Yotsurugi, the only biological heir to the Yotsurugi yakuza family, is caught in a power struggle with his adopted siblings over who will be the next boss. But when a meteorite crashes into Tokyo and people begin manifesting mysterious powers called Astros in the aftermath, their gang war becomes superpowered!

In order to get their hands on Shikaba's piece of the Daybreak Ore, Hibaru and Terasu participate in the Astro Battle Royale, a superpowered tournament hosted by the Japanese Yakuza Association. Hibaru's first opponent is a fireball-wielding fighter from the Ryurin Clan. Will Hibaru be able to punch his way to the top?