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Umeboshi Kinya lives only for the sole purpose to fight and become stronger. But since he became the king of the baston, nobody dares to be measured. Kinya So bored and depressed ... It takes the hair of the beast and heard talk of a potential adversary that it will be a pleasure to go cause! He landed in a boxing hall where it does not happen as it really would have thought ... So? Who is the strongest now?!
Taichi is a fat teenager and a horrible embarrassment to his little sister, Mika. She saves her own image by refusing to acknowledge him in public, but that won't work forever. In order to solve the problem, she enrolls him at a boxing gym, hoping the exercise will make him lose weight. At first, Taichi is very hesitant about the whole idea. Soon, though, his trainer Kurata's tough encouragement makes him feel like he might actually be able to become good at this sort of thing. But while the boxers at the gym accept him as a fattie coming in to jump rope and hit punching bags, will he be able to get them to accept him as a boxer-in-training? And does he have what it takes to become an actual boxer?