Find me as "CryptoExpander" on DeviantArt or Swelltales for more of my stories!  Thanks to Ryver8 for the proofreading!
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BREEEE-ERRT! BREEEE-ERRT!

Jenna groggily opened her eyes, the TV’s alert dragging her from slumber.  "Another bad weather alert?", she thought, before rolling over to peak towards her open window.  She saw nothing but a starry, cloudless sky and still trees through its mesh screen.  "Must be a false alarm" she mumbled, as sleepiness tugged her back to her warm, soft pillow.  Slowly she drifted off once more.

Across the room - unnoticed by Jenna -  an alert ticker scrolled across the TV:

"EMERGENCY ALERT: CHEMICAL SPILL REPORTED IN THE AREA – STAY INDOORS, CLOSE ALL WINDOWS, AND AVOID EXPOSURE UNTIL FURTHER NOTICE."

The message repeated a few more times before the TV returned fully to its regularly scheduled programming.  The flickering light continued to glimmer across Jenna’s small bedroom, casting faint shadows on the sparse furniture of her room: a desk covered with dusty unused college textbooks and a much-cleaner laptop, an office chair, a dresser.  Her closet left open with the door hanging ajar.  The flickering illuminated Jenna as she lay curled up beneath thick covers, her peaceful face framed by messy brown hair that spilled across her pillow.  The night's chill crept through the open window, but her fortress of warmth kept her undisturbed.


Outside, the neighborhood stood largely quiet.  A car's subtle rumble passed occasionally on distant roads to disturb the calm stillness of the subdivision, its headlights carving shifting shadows across the darkened houses.  Far beyond the edge of the light, a silent fog crept closer, an impenetrable misty wall that enveloped the trees in the night as it passed.  The fog slowly smothered and engulfed the neighborhood, dimming streetlights and obscuring houses one by one.  Eventually reaching Jenna's house where it slipped through the open window.  It seeped and pooled into the room without hurry or noise.  Jenna’s sleep remained unbroken as the mystifying chemical accumulated in the air around her.


Below her covers, hidden away from a viewer's eye something strange was occurring.  Her nightshirt - one of Jenna's favorite for years - was rising and falling with her breath, but subtly shifted with each exhale.  The small bumps within slowly blooming into mounds, subtly pulling the fabric tight against her changing form.  Her nightshirt began to stretch taut, pulling up slightly with every new breath, as her growing chest eagerly claimed more and more of the fabric to itself.  As it inched upward, the nightshirt slowly revealed Jenna's midriff, and her belly button soon peaked out to join it.  The fabric crept and crept until the now-mountains contained within demanded release and began to strain against the old and worn shirt.  The tension, and stretching stimulated the dark nubs at the tips of Jenna's breasts, and they tented against the fabric.  The shirt was drawn tighter and tighter, squishing into the pliant udders it was desperately trying to contain.  Its old, worn form was not suited to the task of holding off the deluge of boob it was facing, straining against it's increasingly large foe.  Too much to bear the shirt's stitching began to fray, as individual threads were separated apart.  Jenna's mammaries excitedly claimed the new free space for themselves - pouring into the gaps and making them wider and wider until - RIIIIP - the shirt tore asunder and released the heavily-compressed titties contained within.


 Jenna murmured and tossed a bit in her sleep to the sudden movement of her stupendous chest, but the heavy sleeper slumbered on.  With her nightshirt defeated her greedy breasts refused to remain contained, softly enveloping her right arm and poking into the covers.  Jenna's fortress of warmth finally began to move as more and more Jenna was stuffed into the confined space.  The blanket, like her shirt before, began to have it's slack pulled away, slithering across the bed until Jenna's sock-covered feet slipped out from below their shelter.  As more and more of Jenna's body began to be exposed to the chilly air, Jenna finally began to stir, sleepily-kicking in a vain effort to find her blanket again.  The fog continued to pour through the window and gather, seeping into every corner of the room.

 

BREEEE-ERRT  BREEEE-ERRT


Jenna finally stirred awake.  The TV was blaring, her legs were cold, and something warm and soft smothered her right arm.  "Wha -?" she mumbled, yawning and gently opening her eyes.  She squinted and blinked, but couldn't see much in front of her.  She felt movement against her chest and her feet were cold from where the covers had slid nearly up to her knee.  Her brow furled and she moved to push whatever was pinning her right arm, but found the mysteriously pliant object was below her covers - and she in turn felt her hand jabbing into herself.  "What the hell is this?... It almost feels like... me?... Is this a dream?"  Yanking off the covers to unravel the mystery, she finally could see what was happening before her.  Her chest was simply massive, obscuring most of her body - and so large even her nipples were out of sight - and probably beyond her reach.  With a panic she attempted to sit up, her weighty chest impeding her every motion. Struggling to a kneeling position, her neck craned every which way looking for her phone, for the TV, anything that could help her - before noticing that the ticker still flashed warnings to stay indoor and to avoid exposure.   "Avoid Exposure? To what....?!" The thought hit her.  "My window!" she epiphanized as she shifted suddenly towards it to see a strange mist obscuring her neighbors' houses and the streetlight.  "The fog!" she mused aloud.  While Jenna was distracted figuring out her situation, her excited breathing had seen her steadily inhaling more and more of the bust-boosting chemicals, and her growth rate soon followed suit.

 

As Jenna's bosom visibly grew before her eyes, she realized she needed to get to the window as soon as she could.  Experimentally hefting her chest upward, she found the weight and softness of it made it incredibly awkward and unwieldy.  Her breathing continued to speed up from the exertion under the unfamiliar burden, as her breasts shifted and wobbled unpredictably.  Wholly unused to having tits that weighed more than half of the rest of her body, she struggled to brute-force them forwards in a controllable manner.  She was going to have to think this through or she may not be getting to the window at all!

She eyed it again.  It wasn’t that far - just a few steps once she got off her bed.  Jenna formulated a plan and began to shift and drag her heaving chest to the edge of the bed, thinking she could slide off and get below them for better leverage.  She carefully climbed off, braced herself, and adjusted her weight carefully - all to prepare to rest her massive breasts onto her knees.  It was for naught - as she began to try and place one down, its wobbly, pliant form slipped off of her, pulling her, and her other breast, down to the floor.  


Her right breast hit the floor with a heavy thud that reverberated through her, its soft and squishy form acting like an amplifier.  She barely had time to process the sensation before her left breast had joined it - with the rest of her smacking face-first into her own cleavage.  "OoOoHhh!" she yelped - her voice bore the tone of habit, but also betrayed a touch of pain and something more - as the triple-impact left her breathless and gasping for air.  She lay, huffing and puffing, reveling in what just happened, as her bosom marsh-mellowed into her arms and legs. "Shit!", she shouted.  "This is getting out of hand!" - jolting upright as her bosom began pressing into the bedframe too. All attempts to lift her ponderous orbs failed - they were stuck on the ground.  Instead she strained hard to push against the bed and floor, pulling her bust in an exhausting deep drag motion that burned at her legs.  Each strenuous motion made small progress towards her goal, but also encouraged her sizeable chest to grow further as it began to rival her bed in height.


She developed a rhythm, alternating back and forth between hugging one breast and tugging it with all the force she could muster, to repeating it again with the other it.  Every new hug and tug cycle she found herself sinking deeper and deeper into the pliant udders. Her legs trembled with every exertion as her tits swelled larger and larger - too much longer and she was going to be too big and heavy to move at all. "Come on!" she grunted as she took another step, "Just a bit more!"  Her foot slipped on something.  "Shit!", she shouted as she fell.  Her grip held tight against her udder, and the force pulled her back into its soft embrace.  Jenna reached down, feeling with her hand, to find her assailant.  It was a bra, comically small and useless for her current - and growing - size. "Really? Not even on me and still a pain in the ass?  Won't be needing you anymore."  Jenna frustratingly chucked it across her room.  It soared through the air, briefly passing her still-erect nipples - hardly looking large enough to cover one.  


The window was close.  Just barely an arm's length away, if she could stand up all the way - but Jenna's knees shook and her chest refused to budge any longer. Her expression softened with a look of defeat. She was so close, but the relentless growth of her breasts had beaten her. As before with her clothes, her greedy tits desired more - and began to fill the space around her.  They sprawled across the floor, and began to spill over onto the bed - displacing it with her new pair of beds.  

As her chest began to run out of room against the floor, it continued to rise up and over her bed and nightstand as it rose higher and higher.  Jenna noticed the changing movement, no longer feeling pulled down by her chest.

With great effort Jenna pulled herself up to stand again - and reached.  Stretching as far as her breasts would allow, the window latch was still a hand and a half away.  Jenna relented, her triumphant form deflated and foiled by her inflating bosom.  Exhaustion overwhelmed her as her adrenaline subsided. As her panic abated to tiredness she sunk into her breasts.  She was reluctant to admit it - but they were soft, warm - even comfortable.  Had this been another day, another circumstance, perhaps she would have even enjoyed what was happening to her.  She took a few moments to rest and focus on the sensations of her new and changing form.  A small smile formed on her lips.

Across the room her tits eagerly seized more and more space.  Where they once pressed the fabric of her night-shirt and covers outwards, they now found furniture indenting and sinking into them instead.  Jenna could feel a swirl of new sensations: how her cold and hard furniture would heat up under her bust's radiating warmth.  The piles of the carpet tickling her underside, the splintering of her bedframe, her nipple jutting into the far wall and its sister poking into her open closet - where it poked at shirts far too small to even contain the giant nub.  As she continued to explore her changing form the house groaned from the unexpected pressure.  There was simply too much Jenna in too small of a space, and her bosom began to push her back towards the wall she had so desperately been trying to get to earlier.  Jenna continued rubbing and hugging her chest as it slowly bubbled back in small spurts, until she felt something cold and hard hit her back.  The wall.

 

Jenna's expression hardened as she snapped out of her growth-happy trance.  How long had she been playing with herself?  Looking to the window, it was close, but the swell of her right breast was in the way and the pressure prevented her from moving it.  Jenna instead peered towards the ceiling as an idea came to mind.  She experimentally grabbed holds of her bosom, she pushed her exhausted legs against the wall to climb the swelling mountains.  Her legs burned and her hands slipped on the awkward and difficult climb, but eventually she found herself on a pseudo-stable position on her bosom.  Pushing her back to the wall and her feet to her chest, she crept towards the window latch.  "Come on... Just a little more...", she muttered while trying to reach the last inch, the wobbliness of her platform exacerbating the shaking of her tired body.  Jenna's face was one of pure focus and determination, lighting up as her fingers found the latch. 

CLICK

The window released and slammed shut with a loud bang.  She pushed herself back upon her chest and collapsed into their inviting, soft mass. Her body trembled with exhaustion and relief.

 

For a moment, the room was mostly quiet, save for her ragged breathing and the distant hum of the TV.  Jenna lay atop her personal mountains as her growth finally slowed to a halt.  After what felt like hours, she finally began to think of her surroundings.  The flattened remains of her bed and nightstand jutted into her underbreast. The rest of the room was absolutely smothered by her udders, with her desk and chair swept away in the deluge of breastmeat.  Her left nipple felt like it was indented into the wall, while the areola around her right had joined its crown inside of the closet.  Jenna found she was quite close to the ceiling and could see little of the rest of the room past her pliant form.  She carefully climbed a bit higher and could just barely make out the TV over the top of the ridge of her right breast.


What was on the TV caught Jenna's eye, as a news broadcast reported on the chemical spill, a clean-cut reporter speaking calmly against a backdrop of chaos. 


“Authorities report that hundreds of women in the affected area have experienced… unusual side effects. While most cases have been manageable, several more severe incidents have been documented."  Jenna readjusted herself and peered at the TV through her own cleavage to see that it had cut to a scene of a pair of breasts, nipples censored, muffin-topping over the tops of two neighboring houses.  "Cleanup efforts are underway, but the full scope of the spill’s effects remains unknown.”


Jenna let out a shaky laugh, tinged with disbelief and exhaustion.  “Manageable, huh?” she muttered to herself as she sank back into her room-filling chest.  Jenna sighed, gently exploring the swells of her hills, and drifted back to sleep.