A daughter and her husband came back temporarily to Momoko, who lives a lonely life after her husband left his family behind.At first, Momoko spends a lively and enjoyable life with her son-in-law, Kimihiko, who tended to be reserved, but one day she has to take care of Kimihiko, who is sick.Kimihiko, who was touched by her mother-in-law's kindness, came to see her as a woman from that time onwards, and finally entered into a forbidden relationship with her.Two people living under the same roof.Someday the sense of immorality turns into pleasure.