義理の妹に遊び方を教えてもらいます

My stepbrother asked me to teach him how to play a game that I didn't understand, but if I won, he would let me go to his bdsm party tonight with friends. I taught him, but he took out his hard, thick cock and that turned me on a lot, so I continued playing while he sucked me off and fucked me hard until he came inside my pussy.