Fuyuo Shigaraki, a penniless, divorced, down-and-out middle-aged man, needs to earn a massive 3 million yen for the sake of his daughter.

That’s when he encounters a self-proclaimed “high school girl fighter.”

“Hey mister, why don’t you make money through fighting?”

Caught up in her sweet talk, he stumbles into the underground world of brawling…

But this man hides a past no one knows—
He’s a former MMA fighter, the only one in the world who ever tied with the current world champion.

And thus, a new “battle-crazed” warrior awakens—