Yuichi was welcomed into his wife's home as an adopted son-in-law. However, every night, he thinks of his stepmother, Kaori, who is busty and exudes overwhelming sex appeal. Even during his affair with his daughter-in-law, the image of her voluptuous breasts flashes through his mind... Unable to contain himself any longer, Yuichi honestly confesses his uncontrollable desire. However, Kaori, overcome with the joy of being seen as a woman, unintentionally seduces Yuichi with her sex appeal. His lust, which had been fading...