Sister In The Shower

Used to spy on my Sister in the shower. The first time was accidental, after that it was intentional. I had my " friend" start giving me Oral Lovin' while watching Her and wearing her Panties and Bikini bottoms, fantasized that his mouth was Her deep warm pussy... This went on for years and even now, I still become erect thinking about it. I still steal and sniff Her Panties. Doing it right now; any one else done this, using someone else's mouth for a vaginal substitute?