Haruya Natsukawa, a university student, starts a part-time job as a rental boyfriend to buy his little sister a game. He receives his first client and heads to the meeting spot, only to be greeted by the beautiful girl he secretly admired at university, Akiba Fuyutsuki. Haruya is surprised, but he finds out that it was actually Fuyutsuki’s sister who booked him and since she had to suddenly cancel, Fuyutsuki came in her place. The two end up going on a date because of the circumstances. Unbeknownst to Haruya, Fuyutsuki had been harboring feelings for him ever since an unexpected incident before she entered university…? Starting with the rental boyfriend job, Haruya and Fuyutsuki, who have mutual affection for each other, slowly close the gap between them. This is a love comedy about two sweetly agonizing individuals making a lifelong contract and pledging their love for each other.