Office worker Mizuki Kamiya is feeling deeply down about her recent break up with her ex-boyfriend Yukihiro Narimatsu. She can't catch a break, having to see him even at the company's anniversary party. Out of nowhere, someone swoops Mizuki off her feet, expressing affection for her... it's the CEO of the company, Keishi Seo! Keishi, only trying to avoid a woman stalking him, has now dragged Mizuki into his troubles. In order to keep her safe from his stalker and keep up the appearance of things, the two agree to a "contractual marriage". The CEO of a company and a worker in the offices of that same company now together, their quiet life as a "fake couple" begins. However, Mizuki becomes drawn to some of Keishi's small personal quirks. Could this be something more than a contract? What will happen to the two of them now that they can't stay apart from each other?