Truth or Dare with sister

Truth or Dare. A game to find out each other's deep, dark secrets, or to get someone to do something crazy. It started off as innocent fun. My step-sister, Shelby, and I were laughing as we told each other about the older men that we crushed on, or the neighbor boy that we undressed in front of. It was cute, it was sweet...until my annoying step-brother came in. "I wanna play," he said enthusiastically. Ugh...I guess it wouldn't cause any harm. But that was a mistake. Our innocent game changed to "How many dicks have you sucked?" Gross. He just jumped right in there. Not matter how much I resisted, he kept telling me I had answer. Fine, I could play dirty, too. But he didn't seem to mind. It's almost like my step-brother was getting off to us answering his really perverted questions. So, I thought it would be smart to, when he asked me truth or dare again, switch over to dare so I wouldn't have to answer anything weird. That's where I fucked up. "I dare you to pull your top down," he said with a smug look on his face. "Can I go back to truth or something?" I asked, completely in shock. Of course not. But things got really interesting. It was every man for themselves. I was plotting against my step-brother and step-sister, and they were plotting against me! My step-brother didn't care either. He was enjoying himself, getting my step-sister to blow him, and fucking us both. To top it all off, if someone wasn't willing to do a dare, they had to do everyone's chores. There was no way I was going to lose. In fact, I had a plan. I was going to make my step-brother get off using my step-sister. Fucked up, I know...but somebody's gotta win.