TRUTH OR DARE

POV: Your younger sister is having a slumber party and one of her friends comes knocking on your door. As she sits on your bed she tells you she was dared to give you her first blowjob. "No way!" You protest at first, but then she begs and whines until you give in if she PROMISES not to tell anyone else. After she sucks you dry, licks you clean, and attempts her first DEEPTHROAT - it dawns on you....Why didn't she just ask if she could lie and say she she gave you a blowjob?
(P.S Plot twist at the end) ;)