Since our step-mom is gone, your big sis has been the matriarch of the family and I've been trying my best to take care of you. But I notice that my little bro has been having some trouble meeting and talking to girls. As the woman of the family, I think it might be because I haven't taught you about girls yet. It's my responsibility to teach you so I show you all the things that girls like to do and all the ways to please them so that you'll feel more confident with women. I suck your cock and even let you fuck me. But being your sis, I can't let you cum inside so you have to use my ass instead.