"You know their fucking each other, don't you?"
"I suspected as much. How do you know for sure?"
"I caught them at it. A few weeks ago when there was that bomb scare at work they let us out early. When I got home and went upstairs I could hear noises from her room. I went in and she was kneeling on the bed with him standing behind her, fucking away. They were making so much noise they didn't hear me, she was facing away from me and he had his head back and his eyes closed. I stood there and watched them for a few minutes until it looked like he was getting ready to cum. God, it bothered me, I know they both looked like they were enjoying it. I was so embarrassed that I quietly closed the door and went back out to the car. I tooted the horn and made a lot of noise before coming in. By that time I got in he was in the kitchen smiling. When I asked him where his sister was he said that he thought she was taking a shower. I didn't say anything because I didn't want them to know I was spying."
"Then, not long after that when you were out of town, I heard a noise after I had gone to bed. At first I thought it was a burglar, but then I realized it was coming from his room. I cracked the door open just enough to see that she was sitting on his face and sucking his cock in the 69 position. I got so wet that I was fingering myself while I watched through the crack of the door. He has a beautiful cock. It's not really big around but its long and straight and he really knows how to eat pussy."
"I guess last Saturday was the final topper. You had gone to play golf and I was going shopping. I went outside and talked to Carol next-door for a few minutes before I left. Then I remembered the blouse that I was going to return and dashed back to get it. I went in through the kitchen door and could hear them in the living room. When I looked in, he was standing in the middle of the floor with his pants and underpants around his ankles and she was kneeling in front of him sucking on that beautiful dick. I just stood there looking at him. He looked straight back at me and grinned. I was awed by what was going on."
"I don't know what got into me. I went in to the room, pushed her aside, knelt down in front of him and began to suck. I was surprised that she wasn't shocked and joined me in blowing him. Soon, while I was eating him she removed by blouse and bra and began playing with my tits. Then she had him lay down on the floor. She helped me take off my skirt and panties and had me sit down on his cock. She stripped and sat on his mouth facing me. He fucked me with his cock and her with his tongue while we kissed and played with each other's breasts. I think I had the first climax but they both came shortly after me. Later on, we all came up here to this bedroom and she ate my pussy while he fucked her from behind."
"Jesus Christ, that's quite a story! I can see why your pussy is so wet now and I guess you can see that it has made my cock hard as a rock."
"Well, that's not quite the end of the story. You see, they want to fuck us, you and I."
"Well, I don't know, she sure has a hot body and she's every bit as pretty as you were at 18 but she is my daughter. How do you feel about it?"
"I know that I should be opposed at, but they are twins and we have always stressed doing things together as a family and they are going to keep doing it anyway. Perhaps we can show them how to get the most enjoyment out of it."
"Okay, set it up."