You will not cum until I let you. I thought you understood that bitch”. Her hair was a mess and she was on the ground with her hands tied behind her...back. Still moving her cunt to masturbate.She looked at me and said, “Please master I beg you. Please. Please let me cum. Please, I will do anything. Anything at all”. She got herself up and tried to touch my boner from her lips and said “Fuck my face master. I will please you. But please let me cum. Pleeaaase.” She was almost on the verge of. Dave slipped me his room key and told me to let myself into their room an hour later. I went to my room,showered then decided what lingerie to wear. I chose a tiny pair of pink panties with black stockings and suspender belt,topped by a cream chemise...hidden by jeans and a sweater.I walked to Dave and Sarahs room and let myself in. Before me stood both of them dressed identically in schoolgirl uniforms. Short grey skirt, white blouse and school tie with knee lenght white socks. Sarah wasn't. .. naughty.”The last word was whispered. Ellen smiled at her cousin.“Your head knows that,” Ellen said, pointing at Marie’s forehead. Then she pointed at Marie’s lap. “Your treasure box doesn’t know. Don’t get me wrong, I would never allow anything to happen between you and Richard. You are far too beautiful to give you an opening. But I cannot fault you for an innocent reaction.”Marie looked at Ellen dubiously. “You don’t mind if I have ... thoughts?”Ellen laughed brightly. “Of course not. I. The girls seemed to really be into the male sexual model he had and the guys either dismissed the whole idea of using a condom or actually paid some attention to what he told them. Rob showed how to properly keep a condom to ensure it was still usable and reliable whenever the time came to pull it out of the foil pouch and use it, and also how to properly handle it to kept the lubricated ones as slippery and lubed up as possible. Rob demonstrated everything from tearing open the foil container.