Brad also started kissing on my boobs which soon turned into sucking on my erect nipples. “Just don’t cum inside me, okay?” I said. “Okay,” ...rad said and then got back to sucking on my boobs. My ass was slowly moving up and down while my son’s cock was feeling so good inside my pussy. “Mom, did you… ever give a… titjob?” Brad asked. “You want to fuck Mom’s boobs?” I asked still riding his cock. “You have beautiful big boobs, perfect to give a titjob,” Brad said. I smiled and got up from his. "What here?" she turned to stare at me, "in the car five miles from home?" Yeah, get naked now," I said with a big smile on my face."What if we get stopped or something," she gasped."Then you'll have to give the policemen a nice time and just hope there are two of them," I said."Yeah right, well I'm not taking my clothes off in public," she stated."Too bad, I was planning to stay the night," I said.The silence between us lasted two miles."Ok stop the fucking car and give me a hand," she said. ”“You don’t have to do anything you don’t want to do, and I promise Steve won’t make it weird. Will you, Steve?”“Nope.”“See! It’s simple. Steve, sit down. Katie, come stand next to me.”“Okay...”“Great. Okay. Now, Steve - do you understand kissing?”“Not really, no.”“Katie, close your eyes. I’m going to kiss you.”“What?? But ... I’m your sister!”“Jesus Christ Katie, I’m not going to enjoy it. This is just to show Steve how it works.”“Yeah, but ... still...”“This is just for teaching purposes,. His back was to me and I couldn’t help but to stare at his firm ass and his back muscles. Carter was well toned, and he was starting to turn me on. I was getting really hot, and I couldn’t hide it as Carter turned around. I am sure he noticed my erection, but he just smiled and didn’t say a word. I headed for the showers and Carter followed. The showers in the gym were a big open room with about fifteen nozzles around the walls. I stepped over and turned one on. Carter stepped to the nozzle.