Aoba Suzuki , who has suffered from asthma since childhood and is in poor health , lives his school life while being treated as a tool for his high school classmate Sannosuke Iwase to relieve stress. He has always disliked the boundless cheerfulness of his classmate Kenshin Akazawa, a young star in the world of martial arts . One day, Kenshin mocks him for having no dreams, saying, "You're empty..." and Aoba cannot forgive him, so he makes it his goal to "punch him once"!? He declares Iwase, who bullies him, to be his "friend" and joins Shark Gym, where Iwase goes. With the help of the gym's president Kanenari Tokiwa and Iwase, he jumps into the world of MMA, the strongest martial art where all attacks are allowed, including strikes, throws, and pinfalls!