And then one day, her metabolism gave out.
In the middle of a run, Iris' body suddenly ballooned, turning into a humongous loli lardmass within a mere second, everything she'd eaten coming back all at once and immobilizing her. The girl's costume exploded into shreds as she grew, leaving her naked, only her shoes, gloves and headgear remaining intact. Her feet kept uselessly wiggling, the girl trying to continue running as she just sat there wobbling, very confused as her brain tried to catch up and process what had happened.
"Huh? Why aren't I going forward?", she asked herself, somehow failing to notice her own heavily fat-deepened voice, "And why... Oof, why do I feel so...jiggly?!"
She flapped her hands and tried to look around, now unable to turn her head very well. She could see a huge landscape of soft, pale, sweat-slicked flesh, but didn't understand yet what she was looking at. She huffed and kept trying to run, only succeeding in making herself jiggle some more.
"Ugh... It's no use, I'm stuck for some reason... Wait, what's up with my voice? ...And are those...giant boobs?!"
She finally started to piece it all together, taking a good few minutes to clue in, helped along by the loud, sloppy churning and growling sounds coming from the enormous mass that was her belly. When it finally clicked, her eyes widened and she let out a small scream, now knowing she was looking at her own body trapping her in itself!
"I... I'm gigantic! I've turned into a blob of blubber!", she cried out, "I'm a pile of pudge! An underage adipose avalanche! I'm... I'm..." She paused for a moment, her expression slowly changing into one of...pleasure! Her eyelids drooped a little as her mouth curled into a sensual smile.
"I'm HOT~!", she exclaimed, grunting as she used all her strength to get her body wobbling again, causing herself to sweat even more, "Oh, I'm so beautiful! My fat is so warm and comfy!" Her hands began grabbing at the air as a heated moan escaped her lips. "Oooh, I wish I could grab my fat... Grab big handfuls of ME and... Aaaahhh...!" She started panting a little as her eyes rolled back, the girl biting her lip and giggling. She was getting unbearably horny over her own immense size!
"Mmmmnnngh, my fault... Mmmmhehehe, it's all my fault that I'm such a big fatty doughball! My own piggish appetite got me here~! Silly Iris, no self-control at all~!", she squealed, eyes rolling further up into her head as she gave out a loud primal noise of raw bliss, tongue hanging lazily from her mouth before running sloppily over her thick lips. All the while, her body continued its wobbling and undulating, sloshing all over, a huge amount of gas erupting from both ends of her as a result. Her asscheeks plapped together, sounding like thunder, her fat little toes wiggled and curled within her shoes, her swollen hands flapped helplessly. It wasn't much longer before she'd flexed and squeezed her fat feet hard enough to make her shoes explode open. Her most important part, buried under the rest of her and just as massively bloated, squeezed between girl and ground, was reaching its limit from all the excitement and stimulation. Just a few seconds more and...
"Mmmmmph~! I... I'm... Aaah! FFFFUUUUUUUUUUUUUUUUCK~!! <3"
The colossal loli meatmass had the first orgasm of her life, and it felt amazing, like thousands of fireworks were going off in her very soul. Her overgrown cooch spurted out massive streams of fluid, soaking the ground beneath her for a good minute or so. After finishing, she sat there in a daze, breathing very heavily, still flapping her hands, but much slower now, drool pouring from her open mouth and cascading down her chin and flabby tire of a neck to pool in her cleavage. All she could see was blackness, as her eyes had rolled so far back that only their whites showed. What felt like an hour later, she'd finally caught her breath, stopped jiggling and gotten her sight back. She smiled, blushing brightly, and blissfully sighed.
"Aaahhh... It's GOOD to be fat~ <3"
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