Click, click, click. The camera snapped in quick succession, Erin and Amanda laughing quietly at whatever Nancy was doing behind my head. Suddenly I felt rather than saw something get really close to the top of my head, and Erin gasped. Amanda on the other hand was grinning wickedly and I knew my sister had just pushed the envelope.
The presence disappeared from above my head and Nancy came into view, rushing over to see the pictures. She'd followed Erin's example, and was now clad in a pale green thong that gave me a great view of her butt. I'm not ashamed to admit that I knew she had a nice ass. I'd seen her in enough bikinis and she'd mooned me from across a room while being silly enough times that I was fully aware of what other guys called her 'bubble butt.' I thought it was more of
