The Underwear

That glowing box creeped Sharline out, and that giant dildo, well she hadn't parted on the best of terms with her first boyfriend and it looked too big to be comfortable, so she went with the underwear, pulling them out and putting them on. Nothing happened at first, they were much too big, she had to hold them up with her hands so they didn't fall off her ass, which she was just about to let them do, when suddenly then shrank to fit snugly, even a touch TOO tight, though not enough to be painful or even really uncomfortable in terms of feeling like they might pinch, just tight enough that you couldn't easily forget they were there, and then the REAL fun began.

Just as soon as they resized the thick flexible plastic part of the panties started to morph and 'grow' invading Sharline's pussy and ass with two rubbery semi phallic appendages.

The one in her butt was tiny compared to the one up front, no thicker than her pinkie, but it still was somewhat painful, however it stopped at once even as the pain first registered and began to instead of forcing itself on her slowly, carefully, and ever so gently, tease at her back door and coat it with some kind of oily lubricant. Sharline's husband had convinced her to try anal a couple of times and she had not enjoyed it at all, but this was a bit different, for one thing the phalus was MUCH smaller than her husband's 1.5 inch tool and for another it was working on relaxing her rosebud slowly and gently not lubing her up and pushing in hard and deep.

Meanwhile up front a much bigger 'cock' was fucking her pussy slow and lovingly, while she stumbled to the exam table she had been sitting on and just lay back letting the panties do their thing. The rod inside her had a big head with huge bumps all around the edge of the glans, pulsing ridges kind of like veins, and was 2" across, stretching her out so nice, but that was not the best part. The best part was a set of five tiny tentacle like things which were playing with her clit and sucking on it with itty bitty suction cups, an utterly alien but indescribably erotic sensation. The big dick was doing the ultimate slow-fuck, each 'stroke' taking about 5 seconds and going in only a centimeter further than the one before it. It was SO GOOD but also maddening, because what Sharleen Really wanted was to have a long hard tool gently but powerfully bumping against her cervix. As if sensing the thought the pantie's member started to fuck her faster, each stroke extending a 1/4 inch further in instead of a centimeter and taking only about a second, till at last it started to bump into her cervix and she came right then and there, groaning hugely.

That was the last thing her ass needed to open to the other phallus, almost like a gigantic clit in it's structure, and it slid painlessly into her rectum. Though there was no pain the member in her butt really wasn't doing anything for her, either positive or negative: Sharline being one of the unfortunate women who lack the extension of the clitoral 'wings' that allow some women to take pleasure from anal sex, and after a minute or so of the shaft back there changing shape with each stroke to try to touch off receptors that just weren't there it gave up and withdrew, to her mild disappointment but greater degree of relief.

Though the panties struck out for Sharline on anal they were scoring HIGH marks on their vaginal proficiency, using tricks like the 'hip swirl' and 'pubic bone grind' even thought they lacked the required parts, but seemed to temporarily form them when called for or fake it for a while when they needed to. She came three more times over 20 minutes and was quite blissfully fogged up when the sensation finally got too intense to be wholly pleasurable after her fourth orgasm and the panties returned to their quiescent state.

She basked in the euphoric afterglow for 10 more minutes before Margret came back in again. "Well now dear, aren't those fun? I wear a pair myself most days, and they are quite something let me tell you. These are the latest 'self replicating' model, and we will ask you to keep them on until you leave today, they are designed to eliminate the need to remove them for using the bathroom and the like by using nano tech to process human waste into the components and fuel to make new ones and power themselves, you literally never have to take them off for anything! They even can 'open' partially or completely to allow you to have sex with a man, also eliminating the need for separate condoms if you so desire! I'm kind of jealous, mine are an old 'Alpha Delta' model, you have to take them off to use the bathroom or have intercourse which is very inconvenient if you have to pee in the middle of their 'engagement' cycle."