Now in her forties, one would think that her sexual desires would calm down, but Rieko was troubled by a heat rising from deep within her body every day. Moreover, she always let out her urges by fantasizing about her daughter's boyfriend, Koji, having an affair, and her desires knew no bounds... After that, Rieko forced herself to join her daughters on a hot spring trip. Drowning in sexual desire, she sneaks away from her daughters' eyes and boldly seduces him, hoping to make him hers. And Koji, Kokoro by the lewd behavior of an adult woman, repeatedly...