One day, I suddenly found out that my younger sister, who I really like, isn't related to me by blood! It was a shock, but also a great opportunity! Now we could go out together, or do naughty things if we wanted! The rest was up to my sister's feelings, but it turned out that she loved me more than her brother, and in a miraculous turn of events, we ended up in love! Now we could have an open and honest incestuous relationship!