Tonight, I'm alone with my wife's friend...

Mitsunori married Takako, a junior from a club in her university days, and lives a very ordinary life. One day, Takako's friend Ayumi, who was in the same club, came to stay overnight. Mitsunori, who had always loved Ayumi, was unable to control her heartbeat. Mitsunori indulges in selfish delusions, "I wish Ayumi was my wife..." One night, a dreamy big chance suddenly arrived! The train stopped and my wife Takako couldn't come home...