Kyoko Shimada is a housewife living with her husband and son. Her husband has long been absorbed in his work, and after their child was born, he became even more consumed by his job, rarely spending any time with the family. Amid this loneliness, she began masturbating to cope with her emotional emptiness. Night after night, she found solace in self-pleasure, and gradually it became a routine part of her daily life. But one day, her son discovered her in the act... and then he approached her...