Five years after remarriage, Rin lives days that feel unfulfilled. Her husband's stepchild, Kakeru, tends to be a recluse, and there is always a tense silence in the house. One day, Kakeru accidentally sees his stepmother's nipple in the bathroom and becomes aroused. He attacks Rin while she is cleaning, relentlessly tormenting her nipples and confirming their sensitive reactions. Every time she is touched, Rin's body reacts. Though she resists, she begins to feel pleasure. The relationship with her stepson continues right after sending her husband off, eventually leading her to initiate it herself. A dense forbidden drama depicting the decadence and addiction quietly unfolding within a family, with a story of downfall beginning from the nipples.
