No Nut November challenge had just started, and with my buddies we decided to hold on till December. It was going well for the first few days until my stepsister Roxie with with her slutty besties offered us some cookie! Sitting in class in the middle of the lesson, I felt an erection! Nothing I could do about it; my cock was so hard and throbbing. I noticed my sister smirked and reached out her hand to my erect penis under the desk. My cock was about to burst! She grabbed my erect cock and started jerking me off during the lesson. She moved her hand faster and faster, then got under the desk and took my cock in her mouth! She didn’t want the other girls to notice my raging boner so she swallowed my cock as quickly as possible. Her friends sat nearby but noticed nothing. My cock throbbed inside her mouth and very soon I cummed, filling my sister’s mouth up with semen. What the hell was in those cookies? I’ll tell you what – these cookies were a trap. Eat them, and you’d be busting nuts in seconds. These bitches wanted to spoil our No Nut November challenge and added something to the cookie dough. Now all guys at school had erections. Maybe I lost the No Nut November on that very first day, but my sister would pay me back for it! I forced her to swallow the cookie dough as well. She was so aroused that she climbed onto the teacher’s desk, pushed aside her shorts and started playing with her pussy right in front of everyone in class. After that she undressed all the way down and said she wanted to ride my cock and cum on it. Her massive tits bounced in front of my face as she rode me. She groaned and whimpered and when I grabbed her enormous breasts with both hands, she started squirting all over my cock. Then she collapsed back onto the teacher’s desk and I kept fucking her. I lost No Nut November but I fucked my stepsis and cummed all over her big tits in front of my class.