Your sis usually has loud messy noisy sex with her boyfriend and to be honest it kinda turns you on when you overhear it. She comes into your room straight after a session tonight as her boyfriend pounded her and then took off. She knows you heard her and she's riled up and needs more cock. She never realised how big you were until she tried to have a little fun here tonight but it seems to 'hurt so good'. Just as your about to finish, she can hear someone russling around outside and she becomes even more horny, she seems to have a thing for being watched. You pound her into oblivion as she whimpers for you to pound her while her boyfriend who just fucked her is listening.