You were having a sneaky play with your cock at a family party when you are caught in the act by your sister-in-law. She was half shocked at what she had seen, and half eager to get you back downstairs quickly. Your wife has demanded that you come down and join everyone else. Thank goodness it wasn't the wife or one of the guys that walked in. As your sister-in-law doesn't want to go back down without you and have to explain why, she suggests that you should finish quickly, and she will help it happen. Sit back, relax, and enjoy as your sister-in-law empties your balls whilst your wife, her husband, your friends and the rest of the family are all downstairs waiting!