40-year-old Yori comes back from the big city to be a small town librarian at the town she grew up in. There are rumors as to why she came back; she's not on good terms with her parents, and she isn't married. However, Yori is determined to leave her past behind and settle down for a good, quiet, single life here.
Enter former classmate and unpopular kid, Maki Makoto, who is now a doctor and all-around hottie (I guess). He's married, but has loved Yori Itawani since he was a kid. When he sees she's come to town, he pursues her (even though he's married). He and his wife are in a marriage of convenience, and although he won't divorce her, he has no problem with pursuing Yori.
Yori at first protests, but ends up conceding to his persistence, although she has rules: don't text me, don't call me, and pay me. This is not a romantic relationship, as much as you pretend it is.
Their lives play out, and although she ends up relying on him in the same way he's emotionally dependent on her, she doesn't want to fall (for obvious reasons). She ends up meeting someone who checks all (or maybe only most) of the boxes and thinks that she should leave the doctor and pursue this new and safe relationship. She wants to -- rationally -- but she can't help but be drawn to this person, all while regretting it. What will happen to their relationship?
