Gladiator arenas have been present in certain regions of Japan since the Edo era. Wealthy business moguls and traders employ gladiators to participate in unarmed battles, with the victor taking all. Toki Taouma, also known as "Ashura", competes in these arenas and dominates his adversaries. His remarkable prowess in defeating opponents makes him a standout contender among the wealthy businessmen, which includes Nogi Hideki, the Nogi Group chairman.