" We kissed again for a little more then she stopped moving with my cock deep inside her body. "I need you to have sex with someone and I think I foun...d her." Susan's eyes were big and I got lost in her stare as I tried to process what was just said. "Ok......", I said very slowly and suspiciously. I looked at her funny."I know what you like," Susan smirked at me a little.... meaning she knew I liked big chesty girls with curvy bodies. "She's an undergraduate in my research department!" Meaning. Sara was just ahead of us.Cindy finished Sara's filing right after lunch. I spent the day tying up loose ends, making sure everything was at a good stopping point for the five-day holiday weekend. Mid-afternoon, when Cindy finished with Sara, we did a tour of the jobsite, and then headed back to the office trailer. Because I was told, "Get Cindy out of the office until three o'clock."When we walked back in, several of the engineers and the project manager and Sara were standing around a cake. Then she came over to the coffee table in front of me and bent over again. I instinctively looked down her shirt and at that time, I did not realize I was hard and it was showing through my shorts. My sister stood up and looked at me for a moment with an odd look. Then she said, 'I'm going to shower and go out now. I am glad you enjoyed your view.’ Then she went into her room and I heard the shower turn on. At first I wonder I what she meant then I realized my hard on was showing. Oh. ? When she picked it up to examine the buttons,she noticed that it was so sheer that the outlines of her entire body includingher breasts and nipples would surely be seen even with a casual glance.? She blushed completely down to the tips ofher toes as her nipples contracted and hardened.? There was nothing casual in the way herFather would be treating her in the next year.Shestood naked before the mirror as she had done hundreds of times before, buttonight, she realized, everything would.