Naoyuki, a nephew who lives in the house of her aunt Eriko, who has loved her since she was little, suddenly takes an awkward attitude because she is too conscious of her as the opposite sex. On the other hand, Eriko loved Naoyuki and made a motion every time. One day, Naoyuki, who was in close contact with Eriko who came into the room, inflated her crotch with tension and excitement. Eriko, who was sensitive to it, smiled and held a big warped thing in her mouth.