At the airport, Yuu Ono bumps into a man in a dark suit. The man then takes Yuu to meet his employer: Prince Carlo of the small country of Qurdis. It seems the Prince and Yuu share the same face… and the dark-suited man named Brad is none other than the Prince's bodyguard!

Prince Carlo has a request for Yuu, and that is to become his decoy. Fearing for his own safety, Yuu refuses the request. However, when Brad proclaims, "I'll protect you even at the cost of my life…" – why can't Yuu control the wild beating of his heart?!