A couple lives together in a used rental apartment. Two years into their marriage, they've been enjoying a peaceful life—until a peculiar neighbor from the upper floor starts causing problems. This man, with his striking physique, has a tendency to stir up trouble: improper garbage disposal, smoking in shared areas—his disregard for everyday rules is obvious, and it's becoming a major source of stress for the wife. She's serious-minded, active in the local women's association, and increasingly resentful toward the neighbor. Meanwhile, I, her husband, am a passive, herbivorous type who avoids conflict. Unwilling to aggravate her frustration, I've always tried to calm her down with, "Let's not make waves." But this quiet routine soon spirals into a serious crisis.