She suddenly got engaged to her handsome boss at work, and they started living together... But it's a fake engagement! What will happen to them? Shizuha is known at her company as a no-nonsense, mature woman who's very serious about her job, but she's actually socially awkward and has no romantic experience. Her boss, Inori Hatsukura, helps her as she's targeted by a stalker and proposes a contract to her: to live together and pretend to be engaged for three months until Inori moves to the US branch of the company. After much deliberation, Shizuha decides to accept. What is in store for the two of them?