Ryoko, a married woman who lives in an apartment in Tokyo. she has a problem. That is, my husband has become cold recently. She doubts her relationship with the married woman next door, Yumi, who repeats adultery on a regular basis. Yumi seduces Ryoko's husband, Yukio, as if to ridicule Ryoko's jealousy. Knowing this, Ryoko takes revenge by sleeping with Yumi's husband, Shigeru.