A package arrived at the home of Eri, who is sexless and frustrated. She cautiously opened it to find erotic lingerie and a vibrator inside. Without any doubt, she used them after reading the letter that said free trial. However, this was actually a trap set by her son-in-law Hideki, who wanted to possess Eri's large breasts. Hideki, who had been filming Eri's actions, approached her body!
