Author's Note: While this story and its various chapters are primarily incest themed, it will often contain things such as excessive cum, anal play/pegging, and whatever else amuses me at the time. Reader discretion is advised.
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Emily awoke securely cuddled with her naked brother. She reached around to her ass to make sure her brand new, bejewled butt plug was still in place. She couldn't think of a more romantic gesture than Jaime's proposal to her the night before. She was now officially her brother's butt slut. She loved him so goddamn much.
The one curious thing was how empty she felt. She'd gone to sleep absolutely packed full of brother-cum, and it seemed to have vanished. It couldn't have leaked out of her butt with the plug in place, and besides the bed was still dry. Her body must have absorbed it. That was the only possible explanation.
Jaime looked so cute all sound asleep. Emily wanted to let him rest, but she didn't have the willpower for that. She needed to do something naughty to him.
Emily started by licking his hard cock all over. Jaime twitched and moaned, but didn't stir from his slumber. She then had a better idea, and sat down on his face with her pussy right over his mouth. She felt his tongue sleepily probe her slit. Even unconscious, his body wanted to do sexy things to hers.
Emily rode her sleeping brother's tongue for a while before bending down toward his cock again. It was leaking a copious amount of precum, so she started licking it all up. Jaime's sex-juice was so tasty, but there wasn't enough yet to satisfy Emily's craving. She needed to properly suck him off if she was going to get a proper incesty breakfast out of her brother.
Jaime woke up already eating his sister's pussy, with her throat wrapped around his cock. He didn't question this development. It was getting to be the standard state of affairs. He kept licking away at her, while also grabbing her ass with both hands. With one finger, he toyed with the heart-shaped base of the butt plug inside her.
The tongue in Emily's pussy and the plug in her ass both suddenly came to life. Whereas before Jaime had been licking her on autopilot, now dedication and enthusiasm were felt. She moaned around his cock as he licked and sucked on her clit, while simultaneously wiggling her butt plug.
Emily came hard in her brother's mouth. The flood of pussy cream down his throat, plus the involuntary tightening of his sister's lips, made Jaime cum seconds later. Emily expertly swallowed his massive load as fast as he pumped it out. She drank down so much that it started leaking back out her pussy, and then back into Jaime.
The siblings were caught in an endless loop of cumming and swallowing. Everything they drank cycled through their bodies and back out through their cock or pussy, only to then be consumed by the other. They had inadvertently created a perpetual incest machine. They felt a little panicked by the constant flow, and the way it cut off their ability to breathe, but neither could bear to pull their mouth away from the other.
Eventually Jaime shot a burst of mixed cum so large that it knocked Emily's head away. A shower of mixed penis and pussy juices geysered into the air, then rained down on the conjoined sibling bodies below. Emily lay down beside her brother and waited for the flow to subside.
"That seemed biologically improbable," Jaime said.
"Mmm, sexy though," Emily said.
She kissed her brother. His mouth tasted like her pussy. Even though her tummy was stuffed full of cum already, Emily tasted sex juices on his face and couldn't help licking them off. She had to stop when her belly ached in protest.
"I'm all sticky," Jaime said.
"Yeah, me too."
"And we're going to have to throw out another mattress."
"Yep." Emily kissed her brother again. "Totally worth it."
Jaime smiled. "Sure was."
****
After getting cleaned up and dressed, Jaime hauled the newly sex-ruined mattress downstairs. He was going to throw it in the backyard mattress incinerator, but only made it to the kitchen before he had to stop.
His mom and Aunt Krissy were having coffee together at the breakfast table. They were each wearing one of Christine's robes, and everything about them screamed that they'd been having sex basically all day yesterday. Jaime smirked wickedly at the pair of them. Christine blushed and tried to ignore his stare, Krissy didn't seem fazed.
"Good morning," Jaime said cheerfully. "How'd you two sleep?"
"Fine, thanks," Krissy said. "How about getting that mattress out of the kitchen before it drips all over the floor."
Christine mumbled something and refused to look at her son. Jaime kept smiling as he dragged the sex-sodden mattress outside and disposed of it.
"Hey, neighbour boy."
Jaime had been just about to head back inside when he heard Alyssa greet him. She was leaning up against the fence between their yards, with her head and shoulders visible over the top. Her hair was up in pigtails, and her shirt was sufficiently low-cut to reveal some lovely cleavage.
"Hey, Allie. How's it going?"
"Oh, not bad. You and Em didn't catch the bus with me yesterday though. I heard you were out sick and I got kinda of worried."
"Sorry we worried you. It wasn't anything serious."
"Yeah, I figured. You definitely look recovered to me."
Alyssa grinned at the massive tent in Jaime's pants. He was getting used the leering by now, and he was fine with letting her stare if it made her happy.
"Em should be out any minute now, then I guess we'll be ready to go."
"Sounds good. Hang on, let me come over."
Alyssa held on to the top of the fence and hopped up. She got one of her feet up, then swung gracefully over to Jaime's side. She almost made it, except her pants got caught on a splinter and tore completely off her as she landed. She went bright red as she realized her bottom half was covered only by her panties.
"Oh no!" Alyssa squeaked. "My pants have come off!"
"Boy, that was unlucky," said Jaime. "What are the odds a hot girl would end up losing some of her clothing around me?"
"It's this stupid fence's fault," Alyssa said.
She turned and kicked ineffectually at the wooden structure. In doing so, she gave Jaime a good look at her ass, since her panties only partly covered her bottom.