Taiyo Asano is a super shy high school student and the only person he can talk to is his childhood friend, Mutsumi Yozakura. It turns out that Mutsumi is the daughter of the ultimate spy family! Even worse...

Rumors stir throughout the land: when the wielder of the black sword draws his dark blade, all who stand in its path are torn asunder. Köinzell, the mysterious young boy who carries the black sword, undeniably...