my new step-s****r Episode 7: mk3 design

Becki, our fifteen year-old blonde bi-sexual woke up spread-eagled, face-down naked on her bed. She gingerly rubbed her clit and sl**pily pushed a finger into her cunt and was delighted that the numbness from yesterday had worn off. Becki was humping a pillow when big s****r Faye walked in and kissed all down her pretty tanned back and licked into her pale sore bottom.
“Yuck, this tastes of suntan oil and spunk, what have you been up to?”
Becki abandoned the pillow and cuddled Faye as she had since before puberty, wrapping her legs around Faye's and humping her hip bone, whilst giving a full account of the mk2 masturbator she Molly and Gemma had enjoyed on the train and at the seaside. After Becki described the delicious sensations the mk2 made simultaneously in her nipples and clit, she swung her legs around to be fully interlocked with Faye. Faye slipped a short squishy double-ender between their moist pussy lips and pulled hard on Becki's hands to engage it fully into their cunts. Later they showered together, climaxing again as they swapped Mike's shower-head dildo with the pulsating water spray into their clits and g-spots.
Back in Mike's workshop he had uploaded all the monitoring data from the 3 thigh strap computers, and was building up on-screen a three dimensional internal picture of Gemma's cunt from the temperature and moisture readings. He could clearly observe each time she had climaxed and which programmed stimulations caused it. Mike had stored the discarded the three mk2 devices in a plastic bag after the girls left which Pam found and easily identified which had been worn by each girl from the taste of remaining pussy juice. Pam loved the internal heat image of Molly's cunt and arse and super-imposed it onto close-up photos of her dark pubes and bum to create a panoramic series of composite internal/external views. Timmy had never realised from school human biology lessons how thin the wall was between Molly's two openings and how easily deep anal penetration caused her to climax.
Timmy had managed to hold focus on the mk2 in the cart-wheeling video and flashing into view each time Gemma's cunt was above her head. Mike realised the technical need for an internal accelerometer in mk3 to determine which way up the girl is, and measure her contractions directly.
Mike received an order from Molly's games mistress and several of her friends after watching the videos and trying the nipple-ring stimulator in its proper place and attached to their labia. Pam and Mike researched the web for dildo designs, and Pam loved the 'strap-less strap-on' Feeldoe. This was advertised as having a bulbous passive end that fits snugly into her cunt and the active end for probing her partner, leaving both hands free. Mike ordered a genuine model and several cheaper copies for Pam to try out with her adult friends and the girls at the next Sybian Club meeting.
Faye and Becki came over to Mike's and he carefully watched Pam getting sandwiched by the two s****rs wearing bikini tops and Feeldoes, penetrating her back and front simultaneously. After a few changes of position and dildo model they all agreed that the version with an additional bum-hole bulb provided the best fit, which stayed in place even with vigorous fucking and pussy juice oozing down their legs.
This experiment and the internal 3 dimensional data led to the design of mk3 to automatically adjust to any female pubic shape or size, instead of being custom designed for each C-to-A distance. He re-introduced a lightweight hip belt supporting the almost-rigid thigh straps where the self-guided flexible pussy and bum probes connect. The device was completely open front and back to allow plenty of cooling airflow, with all batteries, comms and control devices on the hip belt.
Molly my step-s****r drooled in delight when she pulled on the mk3 prototype a week later, and I filmed her convulsing through its first probing and her rapid climaxes. Once the middle and rear probes had moulded themselves to its owner's internal dimensions the front probe was free to roam around and massage her clit, or under command to search out other cunts, turning into a 'strap-on' penis.
Pam found that the front probe rotated so she could fuck Faye either face-to-face, from behind, face-to-feet or her favourite position - fully interlocked. Any hip-thrusting action was automatically magnified into the 'penis', for pounding the games mistress or could be reduced for fucking very young girls.
Bluetooth was much enhanced, automatically sending the up-skirt videos to anyone in a 20 metre radius, and allowing control from any PC or iPhone; he added WiFi for the Nintendo DSi console.
Mike won a Porn Industry Design Award for mk3, which included the production of an advertising video. A stretched limo from the porn video company arrived to pick him up with Gemma, Molly and Becki; the girls 'chaperoned' by Faye, Pam, me and Molly's mum, and whisked us all off to Bristol for the weekend. In the limo the girls demonstrated the masturbation and fucking features to the young lesbian director, and everyone had rather too much champagne while trying to understand the script. The house in Bristol had a small swimming pool and one studio equipped as a bedroom, and another as a gym.
A pretty make-up girl arrived next morning and gave the girls a full leg-waxing, trimmed their pubes and styled their hair. She had rarely applied body make-up to 15 year olds and was very pleased with disguising the odd spot on Becki's bum and Molly's tummy. She experimented with the best colours for Gemma's dark skin, and made her body glow beautifully under the strong lights.
The first scene was a side view of Gemma naked, propped up on lots of pillows gently stroking the stylus across her DSi. Her taut nipples and lovely breasts rising and falling with her heavy breathing. The camera panned down the bed to reveal the shiny mk3 strap across her hips, and her shaved pubes framed by the thigh straps. Her knees were together and pulled up slightly by short bondage cords from each ankle to a D-ring under the mk3. The camera moved back up the bed to focus on the DSi held between her breasts; the top screen played a porn video of Becki and Molly, while the lower interactive screen had a cut-away profile of her pelvis allowing her to thrash the cuntal and anal probes from side to side using the stylus.
Becki and Molly bounced onto the bed in tiny white panties and pulled Gemma's legs apart to reveal the 3 metallic probes seeking out her juices. After a slow lick up the inside of each thigh, they each straddled one knee, trying to get off and controlling Gemma's vibrators using their own smart-phones. Becki slipped behind Molly having replaced her panties by an mk3, and demonstrated its use as a strap-on dildo, until Molly's bum hurt. Any other ideas of directing the girls were quickly abandoned and the camera man just tried to keep up with the masturbation orgy in the bedroom and fucking scenes by the poolside.
During a break in filming the director was sun-bathing by the pool, when Pam whipped off her bra, and Faye pulled down her bikini bottoms. Pam straddled her face with a well moistened pussy and Faye pinned her down by the hips, inserting a short dildo. While she couldn't move or shout, the make-up girl chewed her nipples and then painted her breasts bright blue.
Molly's mum checked out the exercise cycles in the gym where Mike had replaced a saddle with his own design containing two probes driven by the pedals. Mike stood behind her, supporting her boobs and giving instruction to select a penetration 'gradient' and cycling speed for maximum effect. Mike spurted up her back when she climaxed noisily.
After smearing most of lunch over Mike and licking it off they pulled on some clothes and trooped off to a park to practice hiding behind trees and flashing their tits at old men. They drew quite a crowd of girls as young as ten wanting to know how the mk3 worked and where to buy one.
Back at the house Molly and the make-up girl, who had very small hands, re-enacted the fisting scene that I had found on dad's laptop back in Episode 1.
Editing the final advertising video down to only 20 minutes of pure filth including some of my photographs and film clips was not easy, but very enjoyable for Mike and Pam in their workshop.
The original purpose of the Sybian Club to loan out Molly's mum's expensive masturbation machine was overtaken by the mk3 that everyone could afford, but the ladies still met most months to swap stories and pussy juice.
87% (7/1)
 
Categories: Taboo
Posted by dasx
4 years ago    Views: 415
Comments (2)
Reply for:
Reply text
Please login or register to post comments.
rafael0058
retired
4 years ago
This was some show thanks
4 years ago
ssssoooooooo bbbaaaadddddd but ssssssoooooo gggoooooddd