When I went back home for the first time in a long time, the one waiting for me was my younger sister, who I had a crush on long ago. We used to live like lovers. I was troubled by the forbidden love between my brother and sister, so I ran away from it. But when I went back home, I kissed my sister, who had grown up and become even more beautiful, for the first time in five years, with a promise to only kiss her. However, that didn't stop me, and I couldn't resist the increasingly intense kisses, and I crossed the final line. Once this happened, the two of us could no longer stop, and we fell into a quagmire of incest...