Kiku and Ryuuji Takane are committed to fulfilling their father's dream of becoming boxing champions. Kiku serves as the trainer, while Ryuuji concentrates on perfecting the Boomerang Hook technique as a boxer. Ryuuji grows and matures as he competes against multiple opponents. As the junior high boxing tournament kicks off, Ryuuji faces his rival, Jun Kenzaki, in a highly-awaited match, and the fight ensues.