Tetsuro Miura (Tomohe Miura) and Aji Watanabe (Makiko Watanabe) live together, but unlike ordinary couples, they practice an open relationship and do not interfere with each other's private lives. Tetsuro had a failed marriage and an 8-year-old son Junosuke (Toshio Fuju). Unfortunately, his ex-wife was unable to take care of the children in a car accident, so Junsuke came to Tetsuro and Aji's home to live temporarily for a period of time. Although he did not express too many opinions about Junsuke's arrival, he was very unhappy in his heart. Not only that, the relationship between the rebellious Junosuke and Aji was very tense. He always felt that Aji stole his father from his mother, so that he could not get his father's love. After a series of accidents and twists and turns, Junsuke returned to his mother, but can Tetsuro and Aji start their lives all over again?