You are waiting for your wife to get home and have a romantic, sexy evening together. Your wife's sister walks in on you. She has been having an affair with you and blackmailing you into submission. She is not pleased that you decided you would have sex without her permission. She begins to give you a handjob and tease you. You can't help but cum as your sister-in-law strokes your cock. She gets up with a giggle and leaves you to come up with an excuse for you to tell your wife for why you cant have sex tonight.