"Il y a cinquante ans, le Japon, divisé, entrait dans une guerre civile. Il aura fallu trois ans pour qu'enfin, le pays soit unifié. On appela cette époque 'Edo'. Une nouvelle ère de paix commença... mais ce qui se succéda à la guerre n'avait rien de bien réjouissant... "Fusuke est un jeune écolier de douze ans à l'allure on ne peut plus banale. Casquette vissée sur le crâne, cartable scotché au dos, il est un garçon gourmand, impulsif et il aime à se prélasser sur l'herbe fraîche. Il semble tout avoir du parfait petit élève modèle. Mais c'est bien connu, les apparences sont trompeuses... et là encore, le jeune Fusuke ne fait pas exception à la règle. Sous cet aspect de charmant petit écolier, Fusuke nous cache bien des choses... entre autres le fait qu'il soit un véritable maître de nink?, un art martial surpuissant dont les techniques allient la vitesse du ninjutsu à la force du

The story in Ninku is about an odd-looking 12-year-old boy named Fuusuke (Fuusuke of the wind (????, Kaze no F?suke?)) who is a powerful warrior from the Ninku school of martial arts, a style that mixes ninjutsu and karate. It is explained that before the present time in the story that those who could use Ninku were targeted by an evil empire and the Ninku corps were formed to combat the menace. The names of the corps were taken from the twelve Chinese zodiac animals (?? Eto) and each captain of the corps was called the zodiac animal Ninku master (??? Etonin). When the war was over, the Ninku were defeated and almost all of them were killed (except for a few corps' captains) since they were useless and were also dangerous for the rulers. At the beginning of the story, three years later, Fuusuke, the young former captain of the 1st Ninku corps and controller of the wind and Hiroyuki (????), his flatulent penguin, start searching for the other Ninku captains, each of whom can control various elements. However, a new group of Ninku users has arisen and are trying to take over the world. Fuusuke and his penguin must defeat the new Ninku empire with the help of his old comrades.