A doctor who died at a young age due to the metastasis of a malignant tumor to the lungs after cutting his right leg below the knee due to osteosarcoma. The title "Asuka" is the name of the eldest daughter, and "Unseen child" is the child whose wife was pregnant at the time of her death.

Asami Usuda stars as twin sisters, down-to-earth Midori and her uninhibited sibling Aoi. Midori is engaged to a successful man and has a promising outlook for a happy life. However, Midori soon finds her life change suddenly after an unexpected turn of events at a love hotel.