Lynn laughed at that response, it was the perfect thing Lincoln could of said to the prideful girl. "I told you it was a little gross didn't I?" she asked. "It's not gross" Lincoln corrected, "it's just... not you." Lincoln said, reaching his hand out and setting it below Lynn's red basketball shorts on her athletic thigh. Lynn felt a pleasant swelling in her ego, whether Lincoln had meant to or not his words had just scored a home run with her. "Keep watching, it'll get grosser" she assured, but her voice suddenly sounded distant and dreamy, the hand on her leg distracting her focus.
Lincoln turned his attention back to his laptop and the intercepted private video playing on it. He knew he should feel guilty for what he was doing, and he did, but he just couldn't look away. He couldn't help it that violating Luan's privacy this way was so exhilarating, and besides it was all Lynn's idea anyway. It wasn't his fault he had to live in a house with so many crazy girls.
The tiny Luan on the laptop monitor was still on her back; legs spread and attentively pleasuring herself. She was still moving her hand slowly and seductively beneath her white panties, taking her time and enjoying herself. If her intention in doing so was to captivate her audience it was working, the two siblings watched in silence, studying her every move. Finally Luan slipped her fingers into the brim of her panties and silently slid them down to her ankles, exposing herself fully to the camera, before her hand returned to her girlhood and resumed it's activity.
Lincoln was entranced. The longer he and Lynn sat silently and watched the more immersed in what he was seeing he became. His conscience was quietly stepping aside and any nagging concerns were fading as a deeper and more primal part of his mind was taking control. Luan might be his sister but he was still a red blooded young man, and while it was true that he had never thought of Luan "that way" before, he had never thought of Lynn "that way" before either until a certain wrestling match had gone a little too far. He was only human after all.
Meanwhile, on the screen, it looked as though Luan was beginning to get carried away with herself. Her once soft and slow hand movements were picking up speed and intensity. Apparently this was no longer a one hand job as she was going at herself with both her left and her right. Three fingers on her right hand were swirling rapidly in a clockwise circle, rubbing her clitoris frantically, while two fingers on her left hand were plunging in and out below. She was moaning delicately between rapid breaths, chest heaving, her hair beginning to come untangled from her ponytail, her skirt wrinkling, and her undies wrapped thoughtlessly around her ankles. It looked to Lincoln as though she was getting "close".