In which, Irene Bae is the the only heiress of the Bae Empire, she is a spoiled brat who loves nightlife.

Because of a certain night, Irene's parents decide to hire her a bodyguard. But she says that she would only agree to have a bodyguard if her bodyguard would be a girl and she would be Irene's personal slave.

The one who got unlucky of applying to be Irene's bodyguard or personal slave?

The innocent, and naive Wendy Son who didn't know that if she was going to apply as Irene's bodyguard, she would also need to be her personal slave.

Irene treats Wendy coldly, but changes when Wendy starts getting close with her rival, Kang Seulgi.