Business deals are typically concluded through meetings and contracts; however, in the world of Kengan Ashura, companies resort to alternative methods to make their decisions: by hiring gladiators. Yabako Sandrovich's Kengan Ashura portrays a world overflowing with action, violence, and martial arts—one where powerful gladiators have fought in grand arenas since the Edo Period to settle the disputes of wealthy businesses and merchants. Ouma Tokita, nicknamed "The Ashura," is a fighter striving to prove himself as the strongest. Hideki Nogi, a member of the Nogi Group, hires Ouma to fight on his behalf and appoints Kazuo Yamashita, an ordinary middle-aged man, as his manager. The pair is thrust into fights organized by the Kengan Association. Their journey will be filled with ruthless battles against other fighters pursuing the same objective. Do they possess what it takes to become the best?