"Big" Billy Anderson walked up the path to his front door. He turned and waved to his friend who smiled and waved back, honking the horn of her battered car as she drove off. He was arriving back a whole two hours early thanks to Trish. Normally he had to catch two public buses to get clean across their small town from the college to home. Between the half hour wait at the bus station and how many times the buses stopped it cost him a lot of time every weekday.
Billy was surprised to see the sexy red sportscar car parked in the driveway. It belonged to his uncle Matt who was a retired professional footballer. Billy's dad always remarked behind Matt's back that the "guy has more money than sense." Billy's mom Milly would swat her husband on the arm and tell him not to be mean.
To Billy Matt was a great uncle. He always bought the best Christmas and Birthday presents. He loved his uncle very much, and he knew that Matt and Milly had always been very close growing up. Billy remembered his mom telling him how they'd shared a bedroom right through college. She'd only had her own room once Matt had left to play professional football.
So Billy was very excited to see that his uncle had stopped by. He slipped into the house through the garage door (which was always open). Hanging his bag on the hooks in the hallway he wandered into the kitchen, thinking that Matt and his mom would be hanging out there. Finding the room empty Billy grabbed a cold drink from the fridge. Opening it, he took a couple of sips and allowed the heat of the day to drain off him. He was standing looking out of the kitchen window, guiltily watching the cute MILF nextdoor watering her plants, when he heard a banging from upstairs.
Maybe Uncle Matt was helping Milly with some of the DIY that needed doing around the place. Billy's dad was a geek - great at the electronics stuff but not so good at putting up shelves or building furniture. Matt would come over to help his sister on occasion, his vast array of power tools so new and shiny that they made most men jealous.
Billy wanted to see what his mom and uncle were up to. He climbed the stairs, sipping from his can, happy as could be. He was home early, his uncle was here, he had the whole evening stretching in front of him, and his mom and her brother were fucking in his parents' bed...
...wait! WHAT!?
Billy stopped dead in his tracks. His parents had the largest bedroom in the house. The door of it was opposite the top of the stairs. It was wide open and offering the young man a great view of his uncle's naked ass as he pumped hard between the wide spread legs of his sister. And hot damn, if Milly wasn't taking it. She had her head turned to the side, eyes closed, hands gripping the sheets tight as the pro athlete worked his muscular body. If it had been anyone else other than his mom and uncle fucking it would have been the best porno ever.
As it was it made Billy sick. The can felt too cold in his hand. His mouth dropped open. His eyes were wide and unblinking. He was lucky that his uncle was facing away from him and his mom had her eyes screwed up in pleasure as otherwise they would have busted him. He stood stock still for a minute, maybe two. He could not believe what he was seeing. Matt was Milly's BROTHER and he was GIVING HER A SCREWING.
That was disgusting! It was INCEST! And yet Billy could not take his eyes off it. The sight of the siblings screwing was one of the sexiest things he had ever seen. The way the moved together, the way that his uncle heaved and his mom shuddered was captivating. His own body was responding to the sight. His mom looked so hot laying there. She had smooth and perfect skin. Her large and slightly droopy breasts with their soft brown nipples were flopping around. Her thighs and calves were muscular where she wrapped them around her brother to hold him close. Billy could not blame Matt for fucking her, even if she was his own sister. If she had not been his mom Billy would have climbed onto that bed and joined in with them.
As it was he stood on the stairs and imagined it was him between his mom's legs. He could not help himself. He was horny enough to fuck anything like most teens were. His mom changed in his eyes from being the kind and caring figure who had baked him a cake for his eighteenth birthday just last week into a sex object who was as perfect as any porn star. MORE perfect - she was real and here and in his own house.
Billy's cock was straining at the material of his shorts. Like all of his family he was well hung, nine inches and thick with it. When he got hard there was no hiding it, much to his embarrasment. If his mom had looked over then she would have seen his rock hard dickmeat squeezed in the material of his tight shorts. Billy put his hand on it and through the fabric gave it a rub. He was enchanted like a snake by a snake charmer, or a teen by a stripper on a pole.
The sound of a door slamming downstairs was a further prompt to the young man. One of the others was home! Billy snapped back into himself. As the woman who had given birth to him eighteen years and one week ago creamed around her brother's hard dick, he knew they stood a real risk of getting caught.
Billy knew what they were doing was wrong. He still didn't want them to get caught, especially not by one of his siblings. None of them should be home right now but his brother and sisters both worked jobs. His father could have come home early to surprise his wife too.
Billy sneaked up the stairs and shut the bedroom door with a quivering hand. To his horror, as the door caught on the wrinkle in the rug where it always caught, his mom's eyes opened. She looked loggy, sweaty faced and freshly fucked, but she blinked and her eyes widened slightly. Billy finished closing the door. His pulse hammered in his ears.
He had to distract whoever was downstairs! Sure his mom now knew that he'd seen her and Uncle Matt making the Beast With Two Backs but that did not mean he wanted them to get in trouble for it. His first loyalty was still to his mother. Running carefully down the stairs Billy entered the kitchen to find his eldest sister Mary rooting through the fridge. His eyes went straight to her ass. She was wearing tight little running shorts and as she bent forward the cheeks of her fleshy rear poked out of the bottom.
What was WRONG with him? First he had caught his mom and uncle fucking and stood and watched; now he was ogling his sister's ass as she bent over. He moved so he was standing behind one of the dining chairs. The backs were so high that he could lean his forearms on it, and it blocked the sight of his still easily evident erection from view.
"Hey Mary. You're home early." He said. He did not want his sister to think he had been sneaking around behind her.
"Oh hey!" She stood up and turned, smiling at him. Mary had such a perfect smile with her clean white teeth and warm soft lips. Billy wondered what those lips would feel like around his...
...No, wait, he didn't. He didn't think that at all, even if his dick did twitch in his underwear at the very idea of how he would love to push it between them. Since when had he been so horny? What was happening to him? Who would he lust after next - the twins?
Hot damn. Twins... so sexy...
"You okay bro?" Mary continued. "You look kinda out of it."
