Your sister is doing laundry. When she checks your pockets, she finds a condom. She calls you in and is mad you didn't tell her you were having sex. She sounds jealous...but why would your sister be jealous you're fucking girls unless she wants you to fuck her? Your sister explains that those dirty whores made you use condoms because they have diseases and don't want you to get them pregnant. Your sister will save herself for you and you can get her pregnant if you want.