Plot

39-year-old Yuko is a high-achieving and proud woman whose career ambitions took her from a sleepy part of Amagasaki City, to Tokyo. When she loses her job due to her "high standards" attitude, she loses her drive to do anything and ends up retreating to her family home where she lives as a NEET with her laidback joker of a father, Ryutaro. For years, the two get along until her 70-something old man brings home Saki, his 20-year-old bride-to-be. When the younger woman shacks up with the two, a comedy of manners based, quite understandably, on a scandalised Yuko's "you're not my mom!" attitude ensues as the younger woman takes to mothering her but when crises occur, Yuko truly begins to evaluate just what a family can be.

Yuko is 39 years old and lives in Amagasaki. She lost her job due to unreasonable restructuring by her company and has not worked since then. She lives with her 65-year-old father, Ryutaro. Ryutaro runs a small factory. One day, Ryutaro suddenly tells Yuko that he is going to remarry. He then brings over 20-year-old Saki, and they begin to live together. Saki dreams of having a happy family, but Yuko is embarrassed about having a 20-year-old stepmother and can't accept Saki as part of her family.