Her remarried partner's stepchild is a recluse. A strained relationship where even conversation is difficult. One day, while Mariko was dozing off, he started taking off her panties, peeking at her crotch. Mariko, who noticed halfway through, questioned her son, but he said he just wanted his mother's warmth. From that day on, it seemed that a new relationship between mother and son would start, but it turned out that her son was looking at his mother as a woman.