Sumire was so horny that she got dumped by her boyfriend. One day, while looking for something in her brother Katsuhiko's room, she found a unused shoulder massage ticket that she had given him before. While her parents were out of town on a trip, she was masturbating freely when she discovered Katsuhiko outside the room jerking off to the sound of her own masturbation. Sumire remembered the shoulder massage ticket and this time presented it as a "vagina massage ticket," hoping he would use up all the condoms. During the parents' absence, the siblings indulged in their desires.
