After being cheated on by his older wife and paying alimony for divorce, he remarried a young, tight-bodied woman—on paper, a successful second marriage. But in reality, their married life is failing. Sex has become less passionate than before, and he's grown tired of mechanical, pregnancy-focused intercourse. Today, while heading out to buy a convenience store bento after feeling lonely about a class reunion, he suddenly runs into his ex-wife. Overcome with nostalgia, he invites her home. Reluctantly, she follows. As they catch up on old times, he can't help himself—he suddenly lunges at her just like in the past…