Yagyu Jubei was Japan's greatest swordsman. His skill was legendary, but the one enemy he couldn't conquer was death. Before he died, though, he gave his disciple hope - there would be a successor, and this deserving person would receive all the power and skill of Yagyu Jubei, along with the Lovely Eyepatch.

After 300 years of searching, the disciple finds Nanohana Jiyuu, a rather ordinary girl who has just moved to a new town and started going to a new school. As if going to a new school weren't stressful enough, now Jiyu is told that she is heir to the legendary talents of Yagyu Jubei. And she will have to put those talents to good use and stop the assassins of the rival clan!