The father was a bit younger around 45 and was one for the ladies apparently. I noticed he was always trying to sneak a glance at me when i wasnt look...ing. It was at the height of fashion then for mini skirts and boots with tights. One night i had arranged for night out with some old friends. I got dressed up in short silky blue dress with matching black silky bikini panties, bra, tan pantyhose and white PVC knee high boots. On the way out i bumped into my father in law (Tim) and his eyes nearly. Stephanie was always the exhibionist and as he thrust his fingers deep into her she began to moan into his ear. “Oh, that feels so good, Matt.”“Perfect, okay now I want you both to lay on the bed. Start by fooling around and running your hands across each others bodies. Matt, suck on Steph’s nipples. After a few moments baby, I want you to kiss your way to Matt’s groin.” They needed little encouragement and wasted no time. Matt’s fingers were exploring deep inside my girlfriend while his lips. I had multi-partner sex before but never had a voyeur evaluating my performance. Hmmm! Mister you have just bought the best seats in the house, but you have to pay to play I said, whipping my cock out I forced it into his mouth, he protested but I insisted more, since I had now lost my erection due to him, he would be in charge of getting me nice and hard to fuck his wife, with a couple of slaps to his face while I held his nose, he was forced to open his mouth, I had never had a man suck me. "Sis, I'm sorry but I really get turned on when I think about you and this girl together. I didn't know you were a lesbian but I like the idea, I would even like to watch you two together, even though I know it is wrong."Sarah was strict in her response but inside she loved the idea of him watching, but she couldn't let him know that. "Matthew, I'm shocked", Sarah spoke while her pussy got a little moist, "how can you say those things? I am your sister and you want to watch me with another.