One day, Hotaru, a young wife, is entrusted with the care of her acquaintance's son, Shota. Shota, who loves big boobs, is intrigued by Hotaru's huge breasts from the very beginning. He immediately shows his precociousness, but when it comes to small talk, he can play pranks on Hotaru, who doesn't pay him any attention at all! The acts escalate with tit groping, tit fucking, and creampie sex!