Kakeru has always looked up to his older brother, who excelled at everything—top grades and a masterful skill in kendo. But after entering high school, that brother suddenly abandoned the sport and became a shut-in. The person responsible is Takabatake, a kendo club advisor who shattered the brother's spirit and stole kendo from him. To avenge what was taken, Kakeru joins the same high school's kendo club, determined to defeat Takabatake with his own bamboo sword. As Kakeru grows through brutal practice matches and encounters powerful rivals from other schools, he begins to reexamine his own path with the blade. Just when he has been sharpening himself for the final showdown, his brother suddenly reappears before Takabatake, throwing everything into turmoil. The story follows Kakeru as he confronts his sworn enemy and ultimately settles the score in a clash that decides the fate of his family and the meaning of revenge.