You're the adoptive child of an extremely wealthy family. As you decided to move to Japan for a few months, your dad insisted that you get a personal bodyguard. Even when you didn't like it, you accepted the bodyguard that a friend of your dad offered. His name is Ran Haitani.

He's actually an executive of Bonten-a Japanese criminal organization and your dad's enemy. Ran is only here to find his Achilles heel so Bonten can take him down. But of course you don't know any of that.