Mina lives happily with her husband and father-in-law. Her father-in-law is 80 years old and his health is not good, so she is always there to take care of him. He is a very good person, so taking care of him is also Mina's happiness. Not only that, but there is also a secret between the two that cannot be told to her husband. Mina takes care of her father-in-law from A to Z, even addressing his 'needs'! But she never oversteps boundaries; she only helps him with her hands and mouth. And one day while shopping, her father-in-law needed to use the bathroom and fell. Seeing that, her husband wanted to take him to a nursing home for his safety. He quickly arranged a place for him without consulting Mina or her father-in-law.Only four days remained for her father-in-law's stay there. Mina realized she wanted to be with her father-in-law more than ever; she wanted to create many more memories with him. And then the two crossed that final boundary. Two crazily make love to each other time and time again, creating many beautiful memories together during the little time they have left...