Ryo Tachikawa, a member of the Yokohama St. John’s Academy boxing club, sets his sights on turning pro and reaching the pinnacle of the world. Meanwhile, Gen Genkai—son of the owner of the Honmoku Boxing Gym where Ryo trains—is still a high schooler, yet he spends his days dismantling yakuza syndicates one by one, aiming for the summit of the underworld.