Yasuoka Tamaki is a 39-year-old mature woman. Her husband is currently working away from home, leaving her alone in the house most of the time. One day, her son Shingo invites his friend Yuuji over. Yuuji is immediately captivated by Tamaki's voluptuous figure and becomes fascinated by her M-cup breasts. Shingo notices this and angrily chases Yuuji out of the house. In truth, Tamaki's body holds a powerful allure for Shingo as well—she is the one person he desires most.