Wife Rie (pseudonym) embarks on a hot springs trip alone with her former student. Their intimate encounter ignites a passionate relationship consumed by desire. At 45, she was raised in a strict household where both parents were teachers. Following her parents' advice, she entered an arranged marriage. She worked as a music teacher until her child was born, then became a full-time housewife. After her children grew up, she joined a local choir and reunited with a former student—this meeting awakens her long-suppressed sexuality. Having been in a sexless marriage for over a decade, she repeatedly reaches intense orgasms each time he penetrates her. The reunion overwhelms her self-control, profoundly affecting her emotionally. Their relationship, blending warmth and hidden lust, evolves into a drama of pleasure and fantasy.