Stepsister Started It. Part 2

This was a game to her, and he wanted so badly to make her stop, but it just felt soooo good. He couldn't. His body froze up and he looked down. What he saw was his hard dick, standing straight up towards his face and his sisters smiling, giggling face right next to it, singing "Babbbbby brotherrrrrr..." while her fingertips gently and slowly moved up and down... up and down on his hard dick. He looked over at her ass, trying to take his mind off of what was happening. She stuck her butt up in the air.

"Grab my butt," she whispered, and she smacked her butt.

His left hand shot out and he grabbed onto Bella's butt like someone trying to stop themselves from falling over. Her hand went right back to his dick, but instead of just caressing it, she wrapped her whole hand around it.

"Oh his god..." he whispered again, his breath trembling.

He couldn't believe what was happening. he looked down and saw his sister, staring at his hard dick as she gripped it firmly in her h