Ari Inari, who lives at her parents' house, was looking forward to a trip to Hawaii with her family, but it was canceled due to her father's work. Because she had bought a new swimsuit, she regretted that she started living at home in a bikini. My brother is in agony with his sister in a bikini and can't stop getting an erection! Finally, she can't stand it and ends up committing forbidden incest.