Sekkusu to kaiwa to tsûkin-densha

Yasuo and Reiko are a married couple with good sexual compatibility, but Yasuo is dissatisfied with the lack of enjoyable conversation between them. Due to a strange turn of events, he ends up going to a hotel with a junior colleague of Reiko. Reiko goes to the room of another junior colleague, Nobuko, and gets drunk, and on the way back she meets her old lover, Tamura. Tamura is Nobuko's man. Nobuko also has a colleague of Yasuo, Kimura. In the midst of these complicated intertwining human relationships, the flames of lust begin to flare...