"I know my mom is already teaching my sister how to give a good blowjob. They do that in my mother's bedroom, together with her best friend. I get an erection just thinking about my sister giving blowjobs. One day, my mom wants me to see how good my sister is at giving blowjobs. I'm super excited when I see her with a cock in her mouth, but then she makes my sister stop and tells me that guys like me should learn to give blowjobs too. She pulls my arm and pushes me to my knees. I have no choice, but open my mouth and take the big cock into my mouth. My mother explains to my sister that boys with small penises should give blowjobs too. It doesn't take long before my mom's boyfriend cums in my mouth. I feel ashamed and disgusted when my mother forces me to swallow. The humiliation is not over yet, because she forces me to wear a chastity belt, and my sister gets the key."