Emi now lives alone in the house where she used to live with her son, his wife, and her grandchildren. Her son or grandchild comes home every once in a while, but she usually lives alone and lonely. Her only pleasures are watching TV and masturbating every day. One of her pleasures is thinking about what to masturbate with today. One day, while she was masturbating with a vibrator, her son Hiroshi came home. When Hiroshi witnessed his mother masturbating, he couldn't help but get an erection. The two of them...