father's first love

Yoko was enjoying a single life at her parents' home, but when she turned 40, she decided to live alone in Tokyo. A few days later, Yoko came to Tokyo and happened to meet her first love, Isao, at the company she had come for an interview with. That night, Yoko grumbles that she has not decided where to live, but Isao invites her to come to his house, where he is divorced and lives with his son. Even though Yoko feels bad, she ends up visiting Isao's house, but as soon as she sees Isao's son, Shinji, her memories of her first love come back to life...