Your big sister is home for winter break and wants to have a little bit of fun.. you know, just like you two used to. She comes in your room and sees you're still in bed. She was going to invite you to the mall to do some shopping, but now she thinks maybe you two should cuddle instead. She hops in bed and instantly starts teasing you, pulling her big tits out of her tight dress and rubbing your cock through your pants. Don't you want to have a little bit of fun? It's basically the only way she can enjoy being at home.. plus you two could probably get away with a quickie even though Mom and Dad are home. There's just one condition, you can't cum inside her. She is ovulating after all. She climbs on top of you and slowly slides your dick in her wet pussy. You haven't fucked your sister in so long and you can't wait to be buried inside her. She mentions this is the perfect distraction to the news you two just received. Mom is pregnant again, isn't that weird? Especially since your parents are trying to make it seem like a Christmas present. You can't help but smirk when she mentions mom is pregnant and she immediately catches on that you know something. She stops riding and tells you that if you want her to continue, you better spill the beans. You confess that Mom is pregnant with YOU and NOT dad. Your sister is shocked! She had no idea Mom was into this, too. Plus she's a little jealous that she isn't the one who's pregnant, she was your first after all. She begins riding you harder while mentioning that it isn't fair Mom gets to be pregnant. Maybe you should cum inside your big sister after all, especially since she deserves to be pregnant instead. She IS incredibly fertile right now and you love blowing your load as deep as you can inside her. You tell her you're about to cum but she just puts her tits in your face and begs you to fill her up and make her pregnant - which you're happy to oblige. Once you creampie her she giggles and mentions Mom must not be draining you enough judging by the massive load you just had for your sister. She lays back and lets your cum spill out, suggesting that maybe you two should go for round two..