The Hosoda family moved to a new apartment after getting married. They met the Mukai couple at their new home, and had a feeling that they would live a happy life together. One day, when Hosoda went to greet the Mukais, he was suddenly kissed by the Mukais' wife Ai...!? Hosoda was surprised and confused by the suddenness of the situation, but he was carried away by the alluring Ai's seduction regardless of place or time, and they ended up having a relationship. From then on, he began to milk her semen inside him, day and night, regardless of whether there were people around...