I knew my sister was having sex with her boy friend, because I used to hear her moaning locked up in her room with him. She was 19 I was 16 and kept asking me to have sex with her boy friend's friend that had a crush on me. I also liked him but embarrassed about telling him. I knew she wanted me to have sex with him to keep me from telling my parents about her fucking him when they weren't home. One day she came into my room, grabbed me and told her boy friend to take my clothes off in front of his friend. Told him "here's your chance to fuck her" spread my legs, watched him sucking my pussy and left me naked in the room with him and ended up forced to have sex with him. Felt embarrassed about him seeing me naked and watching him strip in front of me. When he bent me over the bed, grabbed my tits and slid his dick into me and forgot all about prudishness. He bagged me like a horny rag doll and ended sucking him dry and could wait for him to do me again the next time my parents left home.