Bobby and his twin sister are the heirs to a vast fortune. Both now eighteen, they've spent their whole lives getting whatever they want, whenever they want it. Some might say this lifestyle has caused them to grow up...a little peculiar. Especially if they knew what goes on when mom and dad are out of town.
It started on their eighteenth birthday; mom and dad had gone on vacation, leaving them by themselves, the whole big house to themselves. Bobby was sitting watching TV, while his sister, Lindsay, lay on the couch, reading a magazine. Lindsay was wearing a bikini top and jean shorts. Bobby glanced over at her, and then took a longer look. He suddenly found himself compelled to stare at his sister's tits in that top. His heart pounded as he watched them move when she breathed. Before long, he was starting to fantasize about going over there and sucking on his sister's big titties, and this caused his cock to get hard. At that point, he decided "What the hell", and unzipped his pants, pulled out his cock, and started to slowly stroke it.