Even to me, her brother, my adult sister is unbelievably cute. I thought my feelings were ordinary sibling affection until I realized I was in love with her and terrified she would discover I saw her sexually. I kept my desire under control until our parents left us alone overnight. When I finally made a move, she did not resist—she seemed delighted. Once we knew the attraction was mutual, we spent the rest of our time ravenously fucking from morning to night, unable to stop despite what our parents would think.