Story depicts the conflicts and growth of families who live at co-operative houses. Nana Igarashi is 35-years-old and works as a diving instructor. She is married to Daiki who is 32-years-old and works at a toy company. They live in a small apartment, while saving up to buy a house. They enjoy their life. Nana and Daiki decide to buy a co-operative house. They also try to have a baby. Nana and Daiki realize it isn't easy to have baby.