After a night of partying, I came home with my lovely girlfriend and my cute stepsister. While my step sis and I decided to have another one, my girl said that she was tired. We were talking and fooling around when all of a sudden the slim brunette looker of my stepsister started hitting on me and slowly pulling down her shirt to unveil her perky boobs. Before I could get my bearings, my pretty step sister was down on her knees sucking on my hard dick. That would be all fine and dandy had my girlfriend not decided to up at that moment. Little to say that she was not happy with the situation, but my stepsis managed to convince her that she should join us.