Work Text:
It had been a calm, contemplative evening so far for Pamela Isley, the green skinned nature goddess also referred to as Poison Ivy. Seated at her desk in her abandoned greenhouse in the outskirts of Gotham, her plush rear end overflowing off the sides of her chair. Ivy was focused on her task of creating new pheromones using her own unique plant based DNA. In the middle of her note taking, however, the nearby door was slammed open.
“Heeeeey, Pammy! I’m bored!” Harley Quinn shouted as she barged into the greenhouse. The pale white jester woman was dressed in her black and red tank top, with matching tights and elbow length gloves, her blonde hair tied into her signature twin tails.
“Mm-hm, be right with you, babe.” Ivy responded, not even bothering to look up from her desk.
Harley crossed her arms and pouted, annoyed at being dismissed. Tapping her foot, her eyes drifted around the room, at the various potted plants and overgrown vegetation that Ivy created wherever she went. Before long, Harley’s gaze fell upon Ivy herself- notably, her backside. A grin spread across the blonde’s face; Ivy’s butt was large and supple, round and bulging under her weight, her broad hips visible even through the thick jumpsuit she wore, the top half undone and tied around her waist, leaving her green torso bare except for the black crop tank covering her breasts. The sight of her romantic partner often turned Harley on, and that evening was no exception.
With a mischievous smirk, Harley began to tiptoe forward, sneaking up behind the distracted redhead, who was oblivious to the other woman’s plan.Then, once she was in range, Harley dashed forward and gripped Ivy’s thick, squishy cheeks in both hands. “Gotcha!” She declared.
“Ahh!” Ivy cried, shocked and dropped the pen she had been writing with. Harley kneaded and jiggled Ivy’s ass, while Ivy blushed a deep shade of green; both women loved it when Harley groped Ivy’s behind. “H-Harley, s-stop!”
“Aw, but I can’t help it, your booty is too juicy!” Harley teased, before acquiescing and releasing Ivy from her grip. “‘Sides, you’ve been workin’ too long anyways.”
Ivy began to fan herself with her hands in an attempt to cool down from her girlfriend’s physical affection. “I-it’s important work. If I can get this pheromone formula down right, I can make it affect plants even when I’m not focusing on them. Make them stronger, more resilient.”
“Huh. No kiddin’...” Harley trailed off, before a lightbulb went off in her head. “Oooohh! You should do it for me too!”
Ivy looked over her shoulder, an eyebrow raised. “Do what?”
“Make me stronger! Resilient! Beefy!” Harley raised her arms in a double bicep flex, making her thin, lithe muscles sing, meager biceps from years of oversized mallet wielding strong, but undeniably small. “C’mon, I’m tired of just being in charge, I wanna be large too!”
Ivy rolled her eyes, initially ignoring Harley’s frivolous request. However, as Harley continued to do bodybuilder poses behind her back, Ivy couldn’t help but consider the possibilities. Her powers were always focused on vegetation, but she knew her pheromones could affect humans as well (typically men). Redoubling her focus, she leaned over and scribbled a few thoughts and formulas down in her notebook, coming up with a new type of pheromone on the spot.
“Alright, Harley.” Ivy stood up, her large ass jutting out behind her. She spun around, her eyes glimmering and her mouth turned upwards into a wry smile. “But you’re not going to be large. I’m going to make you humongous.”
Harley froze in her most muscular pose, surprised that Ivy would say yes, but didn’t want to look a gift horse in the mouth. “Oh, hell yeah!” She stood tall and placed her hands on her hips. “So what’s on the docket, then? Some kinda super fancy chemical formula or-”
All of a sudden, Ivy lunged forward and embraced Harley, paying her back for earlier and cutting off her words as their lips locked. Immediately, she felt Ivy’s pheromones flood her senses, practically steaming off of the redhead, a heavy cloud of soft, sweet scents pouring down her throat, rising in through her nostrils and coating her skin, completely subsuming Harley in moments. It always felt incredible to make out with her girlfriend, but whatever Ivy was doing to her then was on a whole other level.
On Ivy’s end, she was trying not to let herself get totally lost in the pleasure and instead focused her pheromones on replicating the formula she had written. Harley wanted to get big? She would make her as big as she could.
Harley’s body began to get more defined, her skin tight pants becoming even tighter as her thighs and calves became stronger and thicker. Her arms and torso followed suit, biceps and triceps starting to bulge while her pecs pushed her small breasts forward and her abs carved themselves out of her flat stomach. Her shoulders broadened and her traps rose up next to her neck, which was itself thickening with muscle. At the same time, her body began to lengthen, stretching taller and more powerful as her physique shifted from athletic to Amazonian.
The bigger she got, the better Harley began to feel, her senses sharpening and taking in that much more of Ivy’s pheromones. She wrapped her strong arms around Ivy’s torso and pulled her closer, accepting more of what her girlfriend had to give. Harley’s clothes began to creak as her body steadily improved and became more incredible, seams threatening to pop under the surging of her muscles, growing to a size that would make Wonder Woman seem inadequate. Her gloves began to rip at the elbow as her forearms grew to match her burgeoning upper arms, while her glutes swelled with strength and size, quickly matching Ivy’s in bulk, but much harder, threatening to tear through the tights covering them. Harley’s legs grew longer, pushing her height above 6 feet and still creeping upwards, the same happening to her torso as her tank top was pulled higher, revealing more muscular midriff, a six pack of abs growing outwards. Ivy had to crane her neck upwards as Harley grew taller, even as the redhead leaned forward on the tips of her toes, their lips touching for as long as possible before finally being forced apart by the height disparity.
“Well?” Ivy smirked up at Harley. “How’s that for a start?”
Harley looked down at herself, admiring her new form. Her chest was jutting out in front, partially blocking her view, tank top stretched as tight as a sports bra by her beefy pectorals. She flexed on forearm and giggled in delight as her glove split open from the rippling muscle underneath, quickly doing the same with her calves and quads, shredding her tights to pieces while her glutes clenched and popped a seam right down the middle.
“Not half bad, Red!” Harley flexed her pecs as well, making her tank top groan. “Harley got hunky! I’m gonna need a way bigger hammer now! Plus a new wardrobe, new workout epuipm- wait.” Harley froze, taking in what Ivy had said. “‘Start’?”
“What, you think this is all I can manage?” Ivy raised an eyebrow.
“Well, babe,” With graceful force, Harley scooped her lover up in her powerful arms, grasping Ivy’s plush ass in her strong grip and easily holding her weight. “You’re gonna have to prove it.” With that, Harley lifted her beloved up to her face and locked lips again, plunging her tongue deep past Ivy’s lips. Enjoying the power her girlfriend now wielded, Ivy activated her pheromones again, this time with even more gusto.
The effects were immediate- Harley began to grow at double the rate of before. Her poor, tattered wardrobe could only rip and fall off of her body as her muscles swelled, quickly leaving her in the nude, which neither woman minded. The arms holding up Ivy grew stronger, denser and larger, veins popping up her biceps as they grew to the size of bowling balls, and beyond. Her quads grew to the thickness of car tires, and quickly graduated to truck tires, making her thigh gap disappear in favor of a wall of leg muscle. Her abs, looking like it had been cut out of stone, grew thicker and wider, making her washboard stomach into more of a taut, strong muscle belly. Shoulders broadened as Harley’s delts and traps grew, her body struggling to make room for all the power packed sinew appearing on it. The clown princess had gone from lithe to beefy, to now massive, bigger than any goon or henchman either woman had ever met, and was still packing on more and more she-beef.
It got to the point where Harley’s burgeoning pectorals, swelling larger than any woman’s breasts could ever achieve, was such a deep shelf of muscle that it was beginning to push Ivy away once again. Before they could be parted, though, Harley easily lifted her comparatively feather light girlfriend upon her pec shelf, the insane sensation of the redhead’s soft ass on her hard muscles making her moan.
On her end, Ivy could hardly believe how huge Harley was becoming. She knew that her pheromones were powerful, but Harley’s transformation was beyond her expectations, nearly a ton of rippling muscle packed onto her growing frame. From her perspective, all Ivy could see when she opened her eyes was a sea of white flesh flowing off of the love of her life, still growing taller, passing seven feet and quickly approaching eight. It was undeniably hot, to turn Harley into a hulking, oversized beefcake, and Ivy could only wonder why she had never tried sooner.
From Harley’s perspective, it was pure ecstasy. She could feel the air pressure change all along her naked body, her skin turning hyper sensitive, as her body continued to transform into a pure and unstoppable engine of feminine strength. It was like ascending to another level of being, all of her senses sharpening further, and Ivy’s pheromones began to become more and more noticeable to Harley; she could taste and smell the chemicals wafting off her increasingly small wife, and almost subconsciously she began to consume more, taking deeper breaths through her powerful lungs.
Harley’s frame was unbelievably filled with muscle, giant tracts of bulging, veiny sinew jutting out in all directions. Reaching the limit of what a human could ever possibly be, Harley’s body evolved past that, her individual muscle groups mashing against each other to form pure, unadulterated mass. Legs turned into tree trunks of muscle, arms turned into boulders connected by huge elbows, and a heaving torso of tectonic plate pectorals and a swelling hunch of back, neck and shoulder muscles turning her silhouette into a caricature of a muscle woman. Every inch of her towering physique was rippling with growing, heavy, overpowering musculature, her form taking up an insane amount of space within the greenhouse.
Before long, Harley could feel her muscles push aside the furniture, the potted plants, and all of Ivy’s lab equipment, her growth demanding more and more domination of the room. Soon, though, the greenhouse wasn’t even enough for her, and she could feel her biceps collide with the walls of the structure, the same thing happening with her traps and the roof. Harley could hardly process her body’s changes, her mind racing to make sense of her unheard of expansion, until she could no longer even think straight- and her body flexed with orgasm, the sexual tension of turning into a behemoth too much to hold back anymore.
As she came and her head went light, Harley felt her body explode in size. The greenhouse was turned to twisted steel and broken glass as her muscles flexed and swelled, packing on meters of meat in seconds. Any semblance of restraint was long gone as her growing body smashed into nearby buildings, demolishing them with the force of her flexing biceps and quads. The earth began to collapse underneath her, her dozens of tons of muscles cratering the ground, but her growth continued so fast that she lost no height, and only continued to grow.
Harley lost track of which of her muscles were crashing into what, as she got so big that even the skyscrapers seemed to get minuscule. Then all of Gotham City. Then the entire state, the continent, until the living explosion of female muscle that Harley had become grew so big that even the Earth itself couldn’t contain her…
“Holy crap, I’m Planet Harley!” She cried out as Ivy broke her kiss.
“Well, not quite a planet.” Ivy chimed in, her face flushed from the effort of blowing up her lover. “But certainly in charge, wouldn’t you say?”
As the post orgasm clarity came to Harley, she realized that her imagination had gotten the better of her. She was not, in fact, large enough to dwarf all of planet Earth, and was instead at the much more reasonable 15 feet tall and made into a round meatball of muscle, filling Ivy’s greenhouse.
Ivy was still sitting atop Harley’s pecs, which were a dozen feet across and more than enough room for the green woman to lean back and admire her handiwork. Harley’s neck was so thick that it practically merged with her towering traps and broad shoulders, her pretty face nearly enveloped by a sea of sinew, jaw bumping into her bulging pecs. Beyond what Ivy could see, Harley’s enormous shoulders led into her biceps, larger than wrecking balls and capable of even more destruction; her forearms were hardly any smaller, tense and round with throbbing meat. Her back, instead of tapering down to her waist, stayed just as massive all the way down, her midsection thick and throbbing, a huge muscle gut of overstuffed abs stuck out underneath her pecs. Further down, her slit still wet with sex juices, Harley’s thighs matched her arms in width, monster truck tires of quads jutting off her exaggerated frame, while her ultra cut calves were like boulders of steel holding her up, her legs pillars of necessary strength to support all of Harley’s incredible mass.
“Heh heh… got a little carried away there…” Harley blushed, uncharacteristically embarrassed.
“I think we both did.” Ivy blushed in turn, trying and failing to take in her handiwork- Harley was bigger than she had anticipated, by several magnitudes. “I can work on fixing this, it just might take some time to get you back to normal.”
“Hey, no rush!” Harley grinned a typical Harley grin. “I toldja, I wanted to be large! Lemme enjoy this!” She resumed making bodybuilder poses from memory, finding them very hard to pull off due to her sheer mass. Ivy chuckled softly at Harley’s efforts- the redhead hadn’t lied after all. Harley was, indeed, humongous.