Anna laughed, having figured both would have said reward as she stepped up between them, glancing down at the sizeable lump in Michael’s shorts as her hips brushed each of them. She grinned wider as both of them flinched as if they had received a small electric shock. “So be it,” she said simply before turning to her daughter; “Sit on the end of the bed Caitlin.” 

The two of them looked at the older woman who although identical to the mother they had grown up with now seemed to be something different. The warm and loving look they usually saw on her face was now replaced with something that could only be described as predatory. Caitlin glanced down at her mother’s skirt which was twisted and seemed to be caught up beneath it exposing most of her left stockinged thigh.

She chewed on her bottom lip as she took the few steps towards the bed and sat down; she was about to smooth her skirt down when she looked into her mother’s eyes once again; instead she moved her feet apart on the floor knowing that the soaking gusset of her underwear was on display. Her chest heaved as she wondered if her mother would recognise the sexy pair of lacy knickers she had borrowed from her. She didn’t need to look at her brother to know he was taking in every detail the stained panties.

“Punishment first I think,” announced Anna and took hold of her son’s elbow leading him forwards towards his sister. It took Caitlin a second to realise what her mother intended and after the flash of surprise appeared on her face a broad grin spread over her lips. Michael didn’t dare grin but his eyes were full of joy as a long hidden desire was about to be fulfilled. Anna positioned him to stand to the left of his sister’s knees and then turned away. For a moment the two siblings wondered what their mother was doing but she simply walked over to Michael’s chair and wheeled it back towards them.

All three were breathing deeply as Anna sat down on the chair and pulled her skirt all the way up exposing the flesh above her stocking tops and then slid forward, one knee slipping between her daughter’s thighs. Caitlin shuddered at the sensuous feel of nylon sliding against her bare flesh and the sight she was afforded of her mother’s pussy dissected by her panties; her inner lips on display, all shiny and red framed by a wet bush of black pubic hair, matted and stuck to her crotch.

Michael fists tightened by his sides as he looked down at the four legs interwoven before him; two bare and tanned against the others dark with nylon but topped with pale, almost pure white flesh by comparison. His cock twitched visibly in his shorts as the two women before him stared at each other’s crotches, their thighs moving fractionally back and forth against each other indicated by the soft squeak of the chair’s wheels.

It had been literally years since Anna had indulged in spanking. She thought about it as she felt her daughter shift forwards so she was sitting on the very edge of the bed trying to press their knees against each other’s soaking crotches. She kept her thighs pressed together enjoying the friction of the pair of young thighs sliding against her own and the exquisite frustration she could see etched on Caitlin’s face. Twelve years; at least twelve she thought as she felt her juices dribble out of her aching quim onto the leather seat and down onto the carpet.

Sean and Anna had indulged in all sorts of sexual behaviour all over the house when they had first moved in; not a single room had been left out including the cramped utility room where he had gently fucked her as she sat atop the washing machine running its spin cycle at full tilt. It was the kitchen and the wooden table though where he had often spanked her ass till it was red and glowing and then drove his cock deep inside her as he would pull her arms back; the stinging heat of her ass cheeks being slapped by his hips always driving her to incredible orgasms. Halcyon days she smiled at the thought and then it had happened; by tiny degrees at first, Michael had come along, not planned but neither a mistake and their shenanigans, as Sean always called it, had become tempered and a little less often till they were generally confined to the bedroom.

Caitlin had arrived within the year and the full time occupation of looking after a pair of small children while on maternity leave and Sean’s business taking off had increased the time between fucks of any description. Of course Michael grew and from a very young age had displayed a natural curiosity which reduced any shenanigans to times when their son was sound asleep or if they were very lucky on simultaneous days-off when both of their children were in nursery. She was sure the very last time they had engaged in a little sexual chastisement had been cut short as they heard the young child totter along the corridor from his room to theirs and Anna had quickly lifted herself from Sean’s lap, his rock-hard cock standing up straight, shiny with her juices where it had been firmly wedged against her dripping quim as she quickly grabbed a dressing gown before the door opened.

Michael the cause of her frustration that night still stood patiently beside the two women, a sizeable damp spot staining his shorts where the copious amount of precum had leaked from his cock’s eye. If he hadn’t deleted the search history regularly on his computer it would have been obvious that most of his excursions into the sexual side of the internet often ended with one type of spanking scenario or other. Even though it increased the risk of getting caught by his parents or his sister, maybe because of it, he’d always wait, watching the entire length of the video clips on Pornhub or the stories on Lush before he would allow himself to ejaculate.

The last year, more specifically his little sister entering the sixth form and the rapid change in her dress styles and an old category being re-instated on his favourite sex story site had caused him to fantasise more and more about his own family. The obvious sexuality of Caitlin was easy to understand but the innate authority that his mother exuded and his fascination with being punished always made his cock and balls ache as he refused to let himself cum till the story or video was over. He knew he’d explode the moment he was given permission by either of the women before him. He glanced towards the door and wondered if his father shared the same secret desire that his mother had kept so well hidden. His cock throbbed as he hoped the three of them would be caught.

Caitlin was desperate, her pussy quivered with a desire for satisfaction and yet she knew the longer she went without, the greater her orgasm was going to be. One part of her mind was in shock at what was happening before her; she couldn’t deny she had a thirst for the carnal but now, suddenly it seemed she was going to learn everything at the hands of her family. So far all she had experienced was a couple of co-operative, “in preparation for boys” as she had suggested, kiss and fondle sessions with her best friend Jolene who had called time before things went too far and then a few fumblings with Mark which had culminated in a very unsatisfactory time on the previous Saturday.

If she’d known he was going to brag about it she doubted she would have let things go so far. In hindsight his lack of skills when it came to her needs and desires had left her wondering if sex was really all it was cracked up to be. He hadn’t even gone down on her after she had taken her first taste of cock as he had promised. She had enjoyed sucking his glans and was only just getting into her stride thinking she quite liked it when he had blown his load without any warning. She’d spat out his seed in a pure reflex reaction before she had realised what had happened. Mark had what she could only call a temper tantrum, berating her for not knowing that she was meant to swallow it all.

He’d stormed off before she’d even had a chance to admit that the few drops she had tasted she actually liked. Her pussy, so far having only had one of his clumsy fingers within it was soaking; poised and ready to orgasm and yet she had made her way home utterly frustrated and, now, not even in the mood to satisfy her own libido. She looked up into her mother’s eyes gazing between her legs, fully aware of her brother’s swollen member less than a foot away from her face tenting his shorts and knew her reward would be anything and possibly/probably everything she wanted.

Anna was impressed with her son as he stood there patiently and yet obviously filled with lust and desire. What the fuck am I doing? she thought and then said “Assume the position, Michael.” She spread her thighs a few inches and looked up away from her daughter’s crotch and into her eyes as she copied her movements. The two of them closed the couple of inches and sighed simultaneously as their knees pressed into the others crotch. Anna’s stocking were instantly soaked as she felt the hot wet secretions ooze through the panties covering her daughter’s mound. The same sensation was occurring between her own legs as Caitlin’s bare knee pressed into her slit already parted by her own underwear.

Michael breathed deeply, leaning forward placing one hand on the bed beyond his sister’s hip and lowered his lap down across the two pairs of legs. He’d seriously though about pulling down his shorts first but as with the videos he’s watched he knew/felt he had to obey only the instructions he was given. His right hand reached down towards the carpet as his hips lowered and the tent in his shorts slipped into the gap between his mother’s right thigh and his sister’s. he gritted his teeth to stifle a groan as their thighs closed tightly together trapping his manhood.

“Well, Caitlin; you’re brother needs to be disciplined!” Anna ordered. Her pussy quivered against her daughter’s knee as she laid one hand on her son’s shoulders and the other settled on the back of his thigh; her nails lightly pressing into the flesh.

Caitlin grinned, astonished at the turn of events and raised her hand and brought it down onto her brother’s ass. Her pussy flinched as if it had been her own ass spanked but the when she glanced up into her mother’s eyes she felt the guilt of disappointment.

“Seriously, that’s not how you slap an ass!” she stated although Caitlin wondered about the way her brother’s cock had flinched between their thighs might have been proof she did just fine. She watched her mother raise her hand and bring it down sharply upon her brother’s other cheek. Michael groaned deeply and Caitlin understood as his hard swollen shaft bucked within its confines between the women’s thighs. A rush of juices soaked Anna’s knee as she had pressed it hard against her daughter’s crotch the moment her hand had connected with Michael’s ass.

“Having said that, my darling daughter I’m not sure your brother is truly getting the full… benefit of his correction” Anna continued; a deep huskiness within her voice. Caitlin exhaled completely as her mother yanked down Michael’s shorts exposing his taut and muscled ass cheeks. “Flesh on flesh is what is called for, try again.” 

This time Michael’s sister showed no quarter and the sound of her hand landing on his cheek echoed around the room. She looked up quickly at her mother’s face to see her lips pursed and her eyelids closed as her juices washed over Caitlin’s knee, Michael squirmed upon their laps as all at once his sister’s hand had landed, stinging his flesh and their thighs had clamped hard around his shaft and, most of all, his mother’s nails had dug deeply into the back of his thigh. “Again,” whispered Anna without opening her eyes and drove her dripping slit hard into her daughter’s knee each time she heard the sharp slap of flesh on flesh.

Caitlin’s right palm stung with each blow as it landed on her each of her brother’s cheeks in turn; she watched his flesh slowly turn red, felt his cock quiver against her thigh and her quim pulse in unison. She glanced at her elder brother’s head hung down, almost touching the floor and her mother opposite her; these were two of the people who should watch out for her, keep her safe and yet she was obeying their perverted and taboo desires. The thought that her reward would be to feel her brother’s cock sliding inside her virgin pussy sent her over the edge.

Anna opened her eyes as she felt her daughter drive her crotch hard into her knee and could feel sticky, warm juices run down her shin. Caitlin’s head was thrown back, the tendons on her neck standing out, her chest heaving as she orgasmed hard. “Fuck, you’re beautiful” Anna whispered as further tiny ‘O’s radiated out from her own slit.

Michael gritted his teeth tightly together as he felt three sets of nails dig into his flesh; his mother’s gripping his thigh and threaded through his hair digging into his scalp and his sister’s as her hot hand grasped his left buttock. He heard her groan loudly and jerk beneath him and the nail on her forefinger dip down into the cleft between his cheeks. He’d told himself that he wouldn’t come until he was told too but it was all too much as he twisted his hips a fraction and Caitlin’s fingernail slid against his pucker.

Anna looked down at her son as he trembled upon their thighs, felt his swollen cock jerk hard seven or eight times and knew he was filling his shorts with his seed. She waited patiently till Caitlin relaxed, her breathing slowing and she opened her eyes. She smiled lovingly at her daughter lifting her hand up from Michael’s thigh and placing it gently atop the younger woman’s still resting on the glowing cheeks between them. “In for a penny?” she asked.

Caitlin let out a long sigh as tiny aftershocks still sparked from the hard nub of her clit; she withdrew a fraction so it was no longer touching her mother’s nylon-ed knee. She nodded in reply and then, a little hoarsely, stated “In for a pound!” Her eyes dropped to the red ass between them, “Does Mickey get a choice?” she asked.

Anna smiled, “I think the two of us were the last to be convinced; is that right Michael?”

Her son turned his head towards her, still fully bent over and bit his lip guiltily, his face blushing; “The dirty little pervert,” stated Caitlin without any recrimination in her voice.

“Indeed,” replied Anna, “stand up please, son.”

He blushed even more and slowly began to straighten up as his mother closed her thigh against her daughter’s and caught his shorts between them. Michael paused and looked down as the clothing, now seriously stained dragged downwards; a brief look at the smile on his mother’s face told him everything he needed to know. He stood up quickly and his shorts were held long enough that his still quite swollen cock sprang free. A glob of his spunk flew from the tip to land squarely on his mother’s thigh.

Caitlin stared at her brother’s cock; the head was covered in his seed, a long string hanging from his foreskin. She licked her lips as she measured it in her mind’s eye against Mark’s, the only other cock she had seen in a state of arousal. Her brother, even though not fully hard beat him on thickness and length. She grinned as she pictured showing it to the cause, or at least partially responsible, of the day’s events telling Mark “That is seven inches!” A small chuckle escaped her lips as she imagined the look she would get in reply.

Michael’s head shot round to stare at his sister as he heard the quiet laugh. “Sorry, Michael” she answered without removing her gaze from his shaft, “Not you, honestly!”

“Please share,” commented Anna as she leant a little closer and took her time examining an almost identical cock to her husband’s; she was slightly surprised that she didn’t feel a shred of guilt or remorse even as she made the comparison. The fact was that she simply wished/desired to feel both cocks within her.

Caitlin copied her mother’s movement as Michael stood there obediently. “Mark, the boy Micky tried to beat up,” she explained “Well, he doesn’t measure up! He might be just about as long as Micky is here at the moment… but not nearly as thick!”

The cock twitched between them and the head started to rise; “Well, in my experience, dear Caitlin, muscles don’t make the man, generally quite the opposite in fact; I think they call it compensating!” Anna replied.

Michael watched as the two women’s head moved closer, their hair tickling his hips as he felt the dried seed on his foreskin crack as the head swelled and it retracted back a fraction exposing the eye within. He couldn’t help himself as his chest puffed out at the thought that Caitlin was more impressed with his cock than Mark’s. He shook his head slightly as he realised that his sister’s honour that he had tried to defend wasn’t quite as pure as he had assumed.

“So this won’t be the first cock you’ve...