Penny was so horny that she did as her brother asked without questioning the request, wiggling her shapely little ass as she stretched out on her belly beside him. Grinning wickedly Mike crawled across the bed and opened the drawer in the nightstand. Penny pursed her lips curiously as she watched him withdraw a jar of Vaseline.
"My pussy's not that sore, Michael," she said softly. "You don't need that stuff to fuck me."
Mike unscrewed the led and looked at her teasingly as he tossed it to the floor. "Who said I'm going to fuck your pussy, baby sister?"
He separated her ass cheeks with his hands, exposing the tightly muscled ring of her asshole. Sticking his fingers into the jar, he withdrew a thick glob of the petroleum jelly. Penny realized what he planned to do to her as he smeared it all over her puckered asshole.
"No, Mike!" She struggled away from him. "Your cock's too big to fuck me there! It'll really hurt!"
"Not it's not, and I really want to do it to you," Mike said. "Now put those pillows under your pussy. That'll lift your ass so I can slide in my cock. Come on, Sis. Do it!"
Penny was afraid of taking her brother's prick up her asshole, but she was so much in love with his cock that she felt she had to do anything he asked. Fearfully she grabbed the two pillows and wiggled them under her pussy, lifting her rounded asscheeks for the invasion of his cock.
"That's right. That's a good girl." Mike extended his Vaseline-slicked finger and pushed it into his sister's asshole, making Penny grunt as he coated the inside of her ass tunnel with the jelly. "You're going to like it, baby sister! You're going to like it a lot."
Then he coated his massive, stiff cock with the Vaseline, and then he tossed the container onto the floor…
"Hold your asscheeks apart," he commanded. "I want to get in my prick."
Fearfully, submissively, Penny grasped her asscheeks and spread them wide. A second later she felt the spongy knob of her brother's cock pushing onto her asshole. His prick separated her tightly muscled ass ring, making her wince as she felt the first stab of pain. Then his cock was boring into her bowels, filling her rubbery asshole with inch after inch of his fucking cock.
"It hurts, Michael!" Penny gasped. She tried to wiggle away from him, but only wound up thrusting her asscheeks up to his cock. "Awww, it's too big for my ass! You're killing me!"
"Just give it a second, Penny," Mike panted. "Just a second more."
Half of his cock was embedded in her asshole now, and he winced as her exquisitely tight shiner sucked and dung to his cum swollen cock. Mike slid his hands under her slim rib cage, firmly clasping her small, firm tits. Then he started to fuck into her asshole much harder, stuffing the narrow fuck tunnel with the meaty thickness of his cock.
"Ungghhh!" Penny's cheeks were flushed, and her face contorted in pain as her asshole was fucked by her brother's burning prick. "Awww, Michael, stop it! It's too big, you're hurting me!"
"You're going to like it," Mike whispered harshly. Harder and harder he fucked into her, until his cock was buried to the balls in the forbidden heat of her asshole. "There! Now wait'll I start to fuck!"
Pulling on her stiff nipples, he lifted his ass and made Penny sigh as his fat cock pulled out of her asshole. Then he fucked back in again, stuffing even more of his prick into her shit tunnel.
Then he started fucking her. In and out his huge cock fucked, seeming to fill her ass with every stroke. Helplessly Penny grunted and bit her lip, struggling to withstand the pain shooting through her ass. She felt submissive, like a slave girl. She had no choice but to submit to the cruel asshole fucking.
"Does it feel good now, Penny?" Mike panted. His hips contracted steadily, fucking her asshole in a steady brutal rhythm. "Don't you like the way my cock feels rooting in your sweet little ass?"
Then Penny realized that it was true, that she did enjoy it. The pain had all but vanished, and in its place was an intense, throbbing pleasure. Her asshole seemed to have a will of its own now, throbbing and clutching, milking the steely hardness of her brother's prick.
"Ahh, Penny!" Mike squeezed her tits and fucked her ass faster, rhythmically packing her bowels with his cock. "Your asshole feels so good…"
"Fuck me," Penny squealed suddenly. She clawed, the sheets and started humping her pussy off the pillows, eagerly lifting her jiggling asscheeks for more of her brother's cock meat. "You're right, it feels good now, Michael! Ummm, I can feel my asshole sucking your dick. Fuck me Michael, fuck my asshole as hard as you can!"
Chuckling at his baby sister's sudden eagerness, Mike quickened the speed of his fucking. In and out his bloated cock fucked. He looked down and watched the veined shaft of his prick fucking in and out of her tightly puckered ass ring.
"Harder, fuck me harder!" Shamelessly horny, Penny thrust her hand under her belly and groped through her pussy curls, squealing as she sank two fingers into her mushy cunt. "Unh, it feels so good! I'm gonna cum, Michael! Fuck my asshole as hard as you can!"
Mike panted and fucked his stone-hard prick furiously into his sister's ass, wincing as her rubbery shit hole sucked convulsively around his cock. Feverishly Penny fingerfucked her pussy, fucking her fingers in and out of her gurgling cunt, rubbing her clit hard under her thumb.
"Cumming now!" she gasped. "Unhh, Michael, you fuck my ass so good! It's burning, it's burning on your fat dick! Fuck meeee, I'm cummiiiinnnngggg!"
It was an even harder cum that the one produced by her first fuck. Again and again the spasms swept through her naked body, pleasuring her pussy and asshole at the same time.
Her asshole throbbed insanely, clutching and sucking and milking her brother's fucking cock. Her pussy juiced all over her fingers. Penny was barely conscious as her brother colapsed on top of her, ramming his big prick to the hilt in her rubbery little asshole.
"I'm cumming too, Penny!" he sighed. "Oh Christ, here it cummmmsssss."
The white cum spurted out of his prick head, gushing deep into his baby sister's ravaged asshole. Penny mewled as she felt her burning ass tunnel soothed by the salty stream of Mike's cum. Hornily she contracted her ass muscles, helping him shoot out every drop of his spunk.
Neither of them noticed that the bedroom door was now slightly open, nor suspected that they were being watched.
CHAPTER FIVE
They were watched by Diane, their mother. Ten minutes earlier she'd gotten up to use the bathroom when she'd noticed strange sounds coming from upstairs. Even as she'd tiptoed up the stairs, and the sounds grew louder, she never suspected that her children were fucking.
But they were. The horny housewife stood in the hallway and looked through the cracked door, watching Mike fuck his cock into Penny's tender asshole. She stood transfixed even as he collapsed on top of her and his thick cum spurted into Penny's ass guts.
Then Diane quietly shut the door and turned away. She felt as if she were in a trance as she hurried back downstairs to her bathroom. Her cunt was burning as hard as ever. She had to fingerfuck. She desperately needed to cum.
Mike's body was lean and hard, and the cock he'd been fucking into Penny's asshole was obviously a very large one. But Diane still didn't feel aroused by him, or she had suppressed the arousal so well that she wasn't aware of it.
What the act meant to her was that if Mike and Penny were fucking it wouldn't be so extraordinary for her to fuck Kenny too.
Her boy. Her sweet, darling son.
Diane locked the bathroom door behind her and sat on the toilet. Throwing the halves of her robe apart, she rubbed her hands on her enormous, stiff-nippled tits, feeling their weight, imagining Kenny's lips sucking them hungrily.