This is the only time when Ai, who works as a female teacher and advisor for the swimming club, can free her mind. It was the pool at night after club activities were over. She was wrapped in the silence of the night and in a wet swimsuit, and Ai, feeling pleasantly tired, didn't want to go home without her husband, so she masturbated in the changing room. However, she is seen by a delinquent student... A student's reckless behavior cannot be stopped by the sight of her voluptuous breasts spilling out of her competitive swimsuit. What Ai didn't know at that time was that the pleasure of being raped would dominate Ai that night...