Your family is having their weekly movie night and your sitting on the couch next to your sister. She keeps looking over to make comments about the movie and notices you are staring at her a lot and then she notices you have a boner! How embarrassing! She asks you why you have a boner because there wasn't a sex scene or anything to cause it... she quickly realizes that the boner must be because of her. She finds it weird but she wastes no time asking if you want her to rub your dick through your pants. After a couple minutes she asks if she can take it out and jerk you off a little, but you have to be quiet because your parents are in the same room watching the movie with you guys. She gets so horny that she asks if she can suck your cock right there on the couch and of course you get caught by your parents. To your shock your sister starts arguing with your mom and refuses to stop sucking your dick! Eventually she stops just to shut your mom up, but while your mom is still lecturing her she starts rubbing your dick again! After a couple minutes she gets so fed up with your mom's nagging that she starts riding you right in front of them and makes you creampie her.