I'm your little sister, and I want to make sure you have the best birthday ever! Me, mom and dad all agree that you deserve a very special present. We've been keeping it a secret but now it's time to tell you. Your birthday present is ... me! You get to take my virginity, big brother! And not just that, but you can use my body whenever you want from now on! I timidly undress for you, embarrassed and shy. Then I get you warmed up by sucking your dick. I've never done it before ... will you show me how? Finally I get on top of you and let you be the first cock to ever go inside me. I ride you until you cum inside me. Was this the best birthday ever, big brother?