Jilted and heartbroken, 20-year-old Kinoshita Kazuya turns to Diamond, a Rent-A-Girlfriend app that leads him to a fateful encounter with Mizuhara Chizuru, one of the talents on offer.

On Chizuru's request, Kazuya goes on a practice date with Sumi, another rental girlfriend. Will he actually be able to help her and stay out of trouble while he's at it?

Chizuru and Mami go on an awkward rental date unaware that Kazuya has seen them together. How can Chizuru handle this situation?