Yoichi, a boy trained by his father in the "Ukiha Kamikaze" swordplay style, has spent all seventeen years of his life living in the mountains, far from civilization. When his father determines there is nothing more to teach him, he sends Yoichi to the city to stay at the Ikaruga dojo to further develop his mental and physical capabilities. Four sisters reside in the dojo, and Yoichi begins a new, more rigorous "training" regimen.