Everyone is 18 . I was a horny teenager and my mom remarried, and all of a sudden I had a hot sister living with me. We were friendly to each other but mostly kept to ourselves. I fantasized about her a lot. I would always check out her panties, sniff them, try them on, and jerk off into the dirty ones. One day after school I was doing my usual, I had her panties on and was sniffing her dirty ones while I jerked off. She was not due home till after practice, but there she was opening her door seeing me laying there totally exposed. Initially she freaked out and was yelling at me, I got up to leave but she stopped me and started making fun of me. Telling me how girly I looked in girls panties, and that it didn’t even look like I had a dick in there(I’m very small). I tried to leave again but she said she’d tell my mom. She wanted me to try on some more underwear so she could make more fun of me. I told her I would if she would. She picked out a tiny thong from the drawer and told me to put them on. As I was changing she took off her jeans and stripped down to her bra and panties. I got so hard I could barely fit in her thong. She asked if my dick even worked and had me start stroking. She was getting turned on and started rubbing through her panties. We were both on her bed at this point and she reached over and grabbed my dick to stroke. I reached over and pulled her panties aside and started rubbing her clit. She was shaved smooth and had such a hot pussy! We both came. Then she told me to get out and don’t go back in her room. I still sneak in and am hoping to get caught again.