You've found out you've got a half-sister you never knew about, you go to visit her and have been spending the past few days at her house. You've been feeling strangely attracted to her, since you never grew up together, she doesn't feel related. One night after dinner, she admits to you she's been having non--sisterly thoughts about you, and feels confused about it. Your cock instantly gets hard, you want her so much. She gets so turned on by your hard cock, she can't resist, its okay, we aren't fully related so it can't be bad can it? She sucks your cock , and rides you. It instantly feels like your body parts were moulded to be together. This can't be wrong, when it feels so right.  (Custom video - Uses the name David throughout)