"Hey, dude," Bobby said, coming to the door.I was hoping to lay eyes on his sister, after all the stories I had heard about her, but this Serena was q...uite an eyeful herself. She was one fine-looking, sleek soul sister.Then, all of a sudden, this slinky blonde with big tits opened a door and walked out stark naked."Oh shit, I'm sorry," she said when she saw me there and retreated back to her bedroom, closing the door behind her.I had settled in and Bobby turned on the TV but it was hard to get. I started to rub myself through the panties and ended up getting onto my sister's bed. I lay down and frantically rubbed myself through the panties. Before long I was masturbating myself very hard and fast through the panties. I took long hard strokes of my erect cock. Before long I was running into the bathroom and letting my cock explode big sticky splodges into the sink. I tidied up the mess and put the underwear back away. Having gotten away with it once, I got more and more adventurous. Carefully holding the glasses that contained their spunk, the twins ran back downstairs and went into the kitchen where they got out the chocolate syrup and a bottle of milk.They poured a small quantity of milk over the thick creamy jism that lay in the bottom of Larry’s glass, swished it around until the cum and milk were mostly mixed and then poured the creamy liquid into the other glass containing Jerry’s jism.They then squirted some chocolate syrup into the thick, creamy, cum laced mixture,. The washroom door opened right when they closed and locked the stall door. Liam looked into her wide, shocked eyes, and he had to hold himself back from laughing out loud. The person, unaware of what was going on, quickly went about her business, peed, washed her hands and left. When the door was securely shut behind the stranger, Hannah burst out laughing, and Liam joined. "Oh boy, that was close." She said. "Yeah... I guess that was a sign that we should stop–" He stopped mid-sentence at her.