Yui, a corporate slave, is enjoying her day off while lazing around in bed. When she finally gets tired of the doorbell ringing repeatedly, she opens the front door and finds a strange man on his knees proposing to her. Upon closer inspection, she realizes that the man is Haruka, a childhood friend she used to hang out with 15 years ago. Haruka says that Yui has met all the conditions she looks for in a marriage partner. It's an unreasonable request that she made up because she couldn't see Haruka as a romantic interest, who proposed to her when they were children. They go on a date, but Yui is confused by how Haruka is completely different from when she was a child. He asks her to fill the gap in the time they haven't seen each other...