Chisato Shoda and her husband have been married for 20 years, but he's so absorbed in his work that he barely pays attention to her. One day, two of his subordinates are invited to their home. Excited at the prospect of being around young men again, Chisato feels genuine joy stirring deep inside. Sensing their youthful presence, her emotions surge uncontrollably, and before she knows it, she's touching the crotch of one drunken subordinate. In that instant, there's no turning back. Her heart has already strayed, and a new shift begins in her marriage...