Romance! A crazy, overprotective brother! And...spies?!

Taiyo Asano has been on his own ever since his parents died and the only one who seems to care for him is his childhood friend and classmate, Mutsumi Yozakura. But Mutsumi has a secret-she is the head of a family of spies! And on top of that, her brother Kyoichiro is dangerously protective of her! To stop Kyoichiro from killing him, Taiyo and Mutsumi must take the ultimate leap-marriage! Because in the Yozakura family, family cannot kill family.

The battle against the crazy Momo is barely over when the Yozakura siblings get a call from Kai Izumo, president of the Spy Association. A meeting of the Gold-Ranks has been called. The agenda? Expelling the Yozakura family for Momo's dark deeds. Kyoichiro is less than pleased. As the meeting heats up, more colorful members of the association's Gold-Ranks are introduced!