"Hey Kristin!" giggled Kelly gleefully, as she saw her long-time colleague enter the Gap store.
"Hi Kelly," replied Kristin, walking casually over to the checkout. Her shift wasn't due to start for another ten minutes and she wanted to catch up on the latest info.
"So, what's been going on?" she continued.
"Oh, the usual," said Kelly with a mischievous smile. "Nothing exciting. Oh, but there is something I want to show you!"
Looking around the store to make sure there were no customers, Kelly left the desk and made her way into the staff area, in the back, beckoning Kristin to follow.
Once they were in the hidden storage area, Kelly pulled the curtain across.
"What's all this about?" quizzed Kristin wryly. "I only have ten minutes, you know."
"I wanted to show you something amazing I learned last night, at Tenko class - raise your sweater for a moment."
Kristin did as she had been asked, revealing her pink belly and small round navel.
"Now, this move is called the Tenai belly buster, but don't worry! It's not dangerous and I know how to reverse it, anyway. Just relax for a sec ..."
Kelly traced her right index finger around Kristin's belly-button and then deftly jabbed the tip inside, tweaking it somehow.
"Okay, now watch what happens!" she laughed.
Kristin dropped her sweater again and waited.
Soon the results became very apparent.
"I .. I feel ... big" she gasped, as her belly started to grow outwards and create a large bump beneath the red sweater." I feel .. pregnant?".
Kelly watched as Kristin filled out, her stomach swelling into a tight pink sphere, but the pressure was rushing into other areas too and her toes also began to expand.
Kristin quickly pulled her sweater over her head and threw it upon a wooden stool, standing in her jeans and bra, as the amazing changes continued.
As both girls watched, the straps of Kristin's opened-toed sandals began to tighten, to the extent that she had to remove them also, groaning as her feet puffed up further.
"Okay, I'm getting a little tight here .." she confided. "I think I'm ready to stop now!".
Kelly watched Kristin's belly-button shifting and swelling, as if she were mesmerised by it.
"Wha .. oh right!" she smiled" I just need to make another adjustment ..."
She stuck the tip of her finger back into Kristin's navel, but was surprised when her finger was pushed back out again, as her friend's belly-button popped out with a squeak.
"Oh my," she said worriedly "Um .. I don't suppose you could .. er .. suck that back in?"
"Are you serious?" replied Kristin with an expression of disbelief. "Hurry up and do the thing. I'm outgrowing my jeans here!".
It was true - her jeans were beginning to split up the sides as her thighs slowly expanded.
Kelly fiddled with Kristin's bulging navel some more, trying to work her finger tips inside it again, but it was now impossible and all she could do was push it gently.
"Kelly!" squealed Kristin, as her swelling feet became twice their usual size. "Do .. something!"
Suddenly, Kelly had an idea - she couldn't reverse the expansion now, but she could speed it up using the helium tank, which was currently being used to inflate balloons for the latest Gap promotion. Maybe she could disguise all this, at least until later when the shop closed, then .. well, she' d have to see what could be done.
She quickly walked over to the tank and picked up the trailing orange rubber hose, which was luckily quite long.
Next she took the nozzle end of it and approached Kristin, who was working helplessly at her own navel with her rapidly bloating fingers.
"I'm sorry Kristin .. but this is for the best," she muttered, swiftly shoving the hose into Kristin's mouth and dashing back to turn the small metal wheel on the tank, spinning it all the way around.
"Ungh?!" muffled Kristin, as a quiet hissing sound rapidly gave way to a much louder, almost deafening one. "Oomph!"
Fortunately for Kelly, it took only seconds for Kristin's fingers to expand and puff up, until she couldn't remove the hose, which was pouring helium into her at such a rate that her belly had already doubled in size and her toes had almost trebled.
With a loud puffing sound, Kristin became an almost perfect sphere, her jeans finally ripping into shreds as she started to float just above the ground.
Kelly finished turning the wheel, as it came loose of it's housing and fell with a tinkle to the ground, the helium now flowing at maximum volume.
Shortly, a pressurised hiss, followed by silence, indicated that the tank was empty.
Kelly tugged the hose from between Kristin's puffy lips to the sound of a loud gasp and groan, then watched as her fully inflated colleague floated to the ceiling, swollen feet waggling feebly.
"Keh ... Kelly ..." she puffed. "Wha .. why ... have I been ... blown .. up?".
For a brief second, Kelly's attention was caught by a box of tacks that had also been left with the promotional paraphernalia, but the idea quickly passed as she rationalised that bursting Kristin would be too risky and possibly quite messy too.
"It's .. er .. for the store promo!" giggled Kelly with glee. "We ran out of balloons and anyway, you're much more novel than a piece of coloured rubber!".
Kristin groaned loudly, as the pressure settled and her feet grew a little rounder.
"But I'm not .. you can't ... I DON'T WANNA' BE A BALLOON!!"
Kelly smiled her mindless smile and walked over to the tacks, removing the transparent plastic lid and carefully taking a fistful.
"Kristin, what do you suppose would happen if I, say, stuck one of these in your toe and pushed real hard?"
For a moment there was silence, only punctuated by a few faint squeaks and squeals.
"You .. wouldn't dare," ventured Kristin. "If you made me .. pop ...."
Before she could finish, Kelly had positioned a tack just beneath her left-most big toe ( which was enormous ) and brushed the point against it, very lightly.
It felt a thousand times sharper than it was, to Kristin, whose skin was much more sensitive than usual.
"ALRIGHT!" she huffed. "I'll do what .. whatever you want! Be careful .. you'll make me .. burst!"
Kelly smiled with satisfaction.
"Okay, first we need to fill you out just a little more - your feet and hands are still retaining their original shape and they need to be much bigger and rounder to make people believe you are a balloon."
Kristin groaned again, her over-swollen toes writhing uncomfortably.
"Luckily," continued Kelly, we also have a tank of hydrogen that should do the job nicely!"
"I .. s .. saw you ... looking at my .. beh .. belly-button .. before ..." puffed Kristin, an idea forming in her mind.
"Do I ... teh .. turn you .. on .. like this?"
Kelly looked into Kristin's eyes for some trace of the scheme that she supposed her swollen friend was trying to implement, but saw only genuine interest.
"Well, you do .. um .. look kinda' sexy," she blushed.
"I cou .. could ... get much .. bigger" managed Kristin, delighted that Kelly was taking the bait. "I could .. double .. thi .. this .. in fact, I feel ... small!"
Unfortunately, Kristin's idea worked a little too well and, before she could convince Kelly otherwise, the hydrogen tank had been set up and she had the hose between her puffy lips once more.
Anxious to fulfill Kristin's suggestion, Kelly opened the valve all the way and watched with obvious pleasure as her colleague began to squeak and grow even bigger.
By the time the hydrogen tank was emptied, Kristin had about trebled in size and was now actually stuck fast between the floor and ceiling, far too big to fit through the comparatively small door which she had originally used to enter the room.
"How does that feel?!" grinned Kelly, very aroused by her colleague's new size and shape.
"F .. feel like .. a .. balloon!" groaned Kristin. "B .. belly so ... big!"
"I suppose you expect me to kiss you now and give you the opportunity to blow all that pressure into me, eh?" quizzed Kelly with a sly smile, kicking up her ankle behind herself and removing her simple shoe.
Her toes writhed inside her plain black tights and she ran the sole of her foot seductively down the side of Kristin's immense belly.
"I'm not as stupid as you think" she continued, her big toe slowly caressing the area around Kristin's huge thigh.
Kristin groaned again.