A series of swords, epic and colourful, which trains the reader in the middle of medieval Japan and brings additional light to secondary characters encountered in the Samurai mother series. A piece of rock beaten by storms, at the borders of Japan; a land without trees that is not on any known map. This is the place where Furiko and O'kane will have to look for their sister Reiko. Quickly trapped, they will have to face the people alone, then a powerful enemy. Will they be able to protect their sister and the archipelago against this terrible opponent?