Tachibana Yosuke is an ordinary husband living an ordinary life with his ordinary wife Misato in an ordinary apartment. One day, Hibiki and her husband move into the apartment next door to the Tachibana family. "What a beautiful wife..." Yosuke falls in love at first sight with the married woman next door, Ririko, and begins to wonder if there is any way to get along with her. Then, suddenly, an opportunity presents itself. His wife Misato is planning a get-together with the Hibiki and her husband next door! Yosuke can't contain his excitement...