Work Text:
“What do you think Mei’s cooked up this time?” Izumi asked, walking down the hallway with Ochako, her girlfriend, master, and best friend.
“Hopefully whatever it is, she managed to work out any explosive kinks before we get there,” Ochako joked, looking up at Izumi, her girlfriend, cocksleeve, and best friend.
Izumi was dressed in the standard attire for a young woman such as herself: a bra that supported, but did little else to cover her massive, head-dwarfing tits, a short dress that stretched from her breasts to her wide, flared hips, not even able to get halfway down her gigantic, cock-swallowing ass. Her thick, muscular thighs were exposed, as well as her pussy; it was both enticing and practical to have all her pleasure spots easily accessible. Izumi was soft all over, perfect for squeezing and folding and fucking.
To her side, Ochako was dressed differently. Her skin-tight shorts did nothing to hide the huge bulge in her crotch, showing anyone that looked at her the fat, foot-long-soft cock draped over the pair of softball-sized nuts. To be fair, they were only that small because Izumi had just drained them of their delicious, thick cum. Beyond that, she wore a simple shirt over her modest chest, one that was tight enough to show off her muscular shoulders while exposing her buff arms to the air. In fact, Ochako’s entire body was muscular, strong, and enduring; an essential component to being a good master to Izumi.
On a whim, Ochako reached up and tousled Izumi’s short, green hair, earning a curious smile from her taller, but far thicker girlfriend.
“I love you,” Ochako said simply, making Izumi’s smile grow wider.
“Love you too,” she replied, giggling a little in a way that made her titanic tits heave and bounce. They were both only about two feet in diameter, which was less than normal, because Ochako had just drained them of their delicious milk before she had gotten the ominous text from Mei.
They arrived at Mei’s lab and Ochako knocked on the door. They heard the scrambling of feet and the door flew open a second later, revealing a very naked Mei—save for her signature goggles—spouting a very massive cock. Both Izumi and Ochako stared in surprise; they knew Mei’s dick well, and it was about seven inches hard, not the nearly two foot long monster that was sitting happily between her huge, perky tits. Furthermore, her egg-sized nuts were no more, swollen to a pair of softballs—much like Ochako’s own—hanging impatiently between her thick, wide hips and thighs.
“What the fuck?!” Ochako exclaimed.
“I know, isn’t it great?!” Mei replied, stepping aside. “Come in, I can’t wait to show you!”
The two walked into Mei’s lab and followed her to her workbench, where she took a seat and spun around before looking at Ochako and gesturing to Izumi. “Mind if I?”
“Course not, go ahead,” Ochako replied with a casual tip of her head.
Izumi immediately dropped to her knees, eagerly opening her mouth. Mei grabbed onto her head and lined it up with her fat cockhead, before slamming her hips forward and Izumi’s head back at the same time, hilting her 21 thick inches down Izumi’s throat and stomach .
“There we go, alright.” Mei picked up a small remote and gestured to a new device a few feet away. “See that? That’s my new baby: Mei’s Magnificent Mass Multiplier!”
Ochako looked at it curiously as Izumi’s wet sucking echoed through the lab. The ‘baby’ looked like a glorified masturbation tool; a wide, circular tube to slide a cock into, and a large bowl to hold balls beneath.
“It does exactly—fuck, this is good. Having a huge cock is great!” Mei shuddered a little as Izumi continued to suck her cock hungrily. “Is this what I’ve been missing out on?”
Ochako laughed, reaching down and petting Izumi’s head. “Yep. Well, that and Izumi’s technique has really improved over the last few weeks. Professor Kayama says she’s never met a more talented and eager woman.”
Izumi moaned needily under Ochako’s praise and the petting, redoubling her efforts on Mei’s dick.
“Anyway, to put things simply, it enlarges dicks and balls. About triple the size, as you can see.” Mei pressed a button, and the device began to power up.
“And you want me to try it?” Ochako asked.
“I’ve clearly already tested it!” Mei answered, gesturing to her crotch. “And you’ve got the biggest dick at UA.”
“Professor Kayama is bigger,” Ochako replied with a shrug.
Mei laughed. “Yes, but we all know you’re still growing. You’ll be bigger than her by next year. And by today if you go over there and stick your dick in that!”
“Fine, fine,” Ochako sighed, shaking her head as she walked over to the machine. She dropped her pants, letting her cock and balls breathe, and casually stroking the former so it would harden. Ochako placed her heavy nuts into the bowl, then watched as her dick grew to its full, fat 18-inch long and nearly four-inch thick glory. The machine groaned a little as she reached full size, as the sides of her cock pushed against the mechanical cock sleeve.
“Now let it calibrate…” Mei began, pressing a button on her remote. “Should only take a few minutes.”
Ochako winced a little as the machine kicked to life, the sheath moving slowly up and down, scanning her dick, while a similar device felt her balls. All the while, Izumi continued to slurp at Mei’s fat dick, doing so well that Mei set the remote down and gave the woman her full attention. Two hands grabbed onto Izumi’s head as Mei began to face-fuck her properly, wet slaps against her full lips echoed along with the sound of Mei’s gurgling balls.
It didn’t take long for Izumi to finally coax an orgasm from Mei, who threw her head back in ecstasy as she held Izumi’s head to her hips with all her considerable strength. Mei’s swollen nuts clenched as her cock audibly discharged thick streams of cum directly into Izumi’s stomach.
Izumi could hardly believe how much Mei was cumming. She was well-versed in how long the orgasm lasted for each futanari she normally pleasured, and Mei was shattering her old record, and not by a little. She felt her stomach filling rapidly with over a gallon of thick, hot cum, and Mei was still not done. It was like a firehose pumping into her gut, and Izumi loved every second; it was like she had a second Ochako now.
She held her hands against her stomach, reveling as it pushed against them, the cum swelling her like a balloon. Her stomach surpassed her tits in size, pushing further out from her body as it touched the floor and began to spread out along it.
Finally, after at least two minutes, Mei’s blasts turned to spurts, then dribbles, then finally stopped. Mei let go of her head and sighed with sublime satisfaction as Izumi’s head slowly slid backwards, releasing the softening cock from her throat. Below her, Izumi looked like she had swallowed an entire person, a sensation she was used to, but not from Mei.
“Damn,” Ochako admired. “You came as hard as I do.”
Mei grinned dumbly at the ceiling as she caught her breath. “Triple size does not mean triple volume. It means much more… This was my best invention. Now, it’s your turn, Ochako.”
Izumi struggled to her feet, her gut already rapidly shrinking as her body absorbed the life-sustaining cum. She felt her hips widen, her ass plump up, and her tits grow heavier as her body converted excess energy into sexual attraction. After all, cum was essential to life, and without a cock and balls of her own, she had to get it from elsewhere. For the one in a thousand children who were born as women, it was the nature of life. Sometimes she wished she was born as a futanari like everyone else, but then she probably wouldn’t be able to spend most of her time with Ochako’s cock inside of her, and she really liked having Ochako’s cock inside of her.
Ochako smiled up at Izumi as she approached and put her hands on Ochako’s shoulders, leaning in and giving her a gentle kiss. Mei finally recovered enough of her senses to look at the remote and see the calibration had finished. With absolutely no ceremony, in true Mei fashion, she pressed the button, activating her magnificent machine.
Ochako’s head flew back as pleasure ripped through her cock, arcing up her spine and exploding in her brain. Fortunately, Izumi’s huge, soft tits were there as cushions and support as her body went limp and fell backwards due to the overwhelming pleasure coursing through her.
Izumi stared in amazement as Ochako’s huge, mind-breaking cock began to grow before her eyes. 18 inches grew to two feet in a matter of seconds, and it didn’t stop there. Mei had placed a measuring tape alongside the machine, letting Izumi know exactly what was happening. She saw it stretch, inch by inch, longer and thicker than she could believe. Two and a half feet, three feet, three and a half, four, and still it did not stop. The machine stretched to its limits as her cock swelled to a foot in diameter at its fattest, and finally finished its forward growth at 54 inches, a full four-and-a-half feet long.
Below, her balls were not left behind. They swelled rapidly, each growing heavier and heavier with every passing second, dwarfing anything Izumi had seen before. By the time they finished, the taut skin was stretched over balls that were nearly a foot in diameter each. The machine sputtered and released Ochako from its grip, who was panting against Izumi.
The first thing that hit Izumi was the smell. Ochako’s balls already had a potent musk that she could smell from nearly a hundred feet away, but this was intoxicating. Izumi felt her nipples stiffening and her body preparing for Ochako with a speed and desperation she had never felt before. Her mind emptied of every single thought beyond her master’s virility.
Ochako’s mind wasn’t doing much better. What Mei had failed to mention was that her futanari hormones would be tripled in strength as well. The smell of Izumi’s arousal and the softness of her body made Ochako’s entire body tense, and she suddenly felt very hungry.
She turned around to face Izumi, knocking another one of Mei’s inventions over as her fat dick swung with her. Her balls felt like they weighed a thousand pounds each, and her legs were struggling to keep her upright, but she was too focused. WIth a rough hand, she grabbed one of Izumi’s fat tits and gave her a direct order. “Milk. Now.”
Izumi’s body responded eagerly, desperate to please Ochako. She felt her tits swelling in real time as her master tore her shirt and bra off with ease, and began to drink. Even her rapid production couldn’t keep up with Ochako’s forceful sucking, but as she drained one, she swapped to the other, giving the first time to make more milk.
She couldn’t help it: Izumi came on the spot as Ochako drained her. Just her touch sent Izumi to the moon.
However, she noticed that Ochako wasn’t quite done growing. Her hormone-fueled body was not just letting the milk lie, but was using it immediately. Ochako’s muscles visibly swelled, growing her from toned to buff to ripped in a matter of minutes, putting incredible strain on her clothing. Her fat stores grew, keeping Ochako pleasurably curvy and smooth, but the strength she was gaining was undeniable. Her body decided that her frame was insufficient for her new dick, and Izumi watched in amazement as Ochako grew taller, finally pulling her mouth from Izumi’s nipple as she reached six feet tall, tearing her clothes to scrap. Before her stood a tall, sleek woman, still curvaceous and delicious, but none could deny the potency of those powerful muscles.
“Amazing!” Mei exclaimed, taking furious notes at the fat-dicked amazon that was now dominating her lab.
Ochako, on the other hand, barely noticed she was there. She leaned down to kiss Izumi deeply, then pulled back and gave her another order. “Get ready to get fucked, slut.”
Izumi obliged as fast as her body would allow. She fell to her knees and turned around, resting on her fat tits as she stuck her ass into the air. Ochako’s lust-dominated mind allowed no hesitation as she lined up her cock with Izumi’s dripping pussy, and began to thrust.
Immediately, Izumi cried out. Her pussy was used to being stretched, but never by something this large. Even so, it accepted Ochako’s tip, and soon, the whole cockhead. Izumi’s brain was blank, breaking under a deluge of constant, overlapping orgasms, but Ochako didn’t stop. She pushed deeper, slowly advancing against Izumi’s back pressure until she could reach Izumi’s hips.
Ochako secured an iron grip and thrust, hilting the entirety of her cock inside her girlfriend, blowing past her cervix and stretching her womb out beyond anything before.. Izumi’s body happily, eagerly rearranged itself to accommodate Ochako, who was using her more like a condom than a partner. Her dick was so massive that, with their hips together, the bulge was pushing out beyond Izumi’s face. Her tits hung to each side of the rock-hard invader, quivering and leaking milk as Izumi tried to comprehend the impossible, foot-thick cock that was claiming her insides.
In that moment, Izumi understood that her body was not hers, but Ochako’s. It was for Ochako’s use and for her pleasure, and she couldn't have been happier. That revelation, that acceptance changed something. Ochako felt Izumi’s body shifting around her dick, tightening itself around her most sensitive parts, as if it was molding itself only to serve her.
“Fuck!” Ochako grunted as she pulled back two entire feet and slammed her cock back home in a powerful thrust. “You’re so fucking perfect!”
Izumi couldn’t speak. She could only moan, whine, and wordlessly beg for more from her mate, desperate not just for her own pleasure, but to serve. All she cared about was Ochako and her happiness.
Intermittent thrusts turned into regular pistoning as Ochako picked up steam, fucking Izumi harder than she could have ever imagined. Her gigantic balls swung weightily, crashing into Izumi’s thighs, heavier and harder with every thrust. Ochako knew they had grown larger as they swelled with cum, but her enhanced muscles barely noticed the additional weight.
Ochako reached out and lifted Izumi up, wrapping her arm around her shoulder as she began to thrust up into her. Izumi’s huge tits flopped around, milk spraying across the lab, but Ochako didn’t care. All she cared about was breeding Izumi and making her feel as good as possible. She relied on Ochako for her life and sustenance, and she took that very seriously. Nobody in the entire world would be as well-fed and cared for as Izumi would be; that she swore.
In a moment of clarity, Ochako noticed that to her side, Mei had given up on taking notes, and was instead vigorously masturbating as she watched. Ochako made eye contact with her, then beckoned her closer. Mei wordlessly, obediently approached, and Ochako reached down, grabbing one of her own ass cheeks, and spread it, revealing her dripping pussy to Mei.
She didn’t hesitate, slamming into Ochako in a single thrust, sending even more pleasure into her mind. Ochako let Izumi fall back to the ground, thrusting into her pussy and sending her huge ass clapping. She grabbed a handful, then gave Izumi a firm spank, making her squeeze around Ochako’s cock.
Every time she pulled out of Izumi’s pussy, she pushed Mei’s cock deeper into her own. Previously, Mei could barely reach her cervix, but now Mei was deep inside of it, stretching her out and adding to her ecstasy.
Mei herself could barely process thoughts. Her mind was still not used to the enhanced sensitivity of her enlarged cock, and Ochako’s pussy was tighter than it had ever been before. She could feel her balls rapidly swelling as Ochako slammed back into her hips, hilting Mei’s cock and almost crushing her beneath her huge, muscular ass as Mei grabbed onto Ochako’s hips for support, or perhaps for dear life.
Seeing her friend turn into a hyper-dicked amazon and then fucking her was too much for Mei, who came for the second time in an hour, this time even harder than before. Ochako felt Mei erupting inside of her womb, and paused her thrusting to enjoy the sensation. Previously, Mei could only bloat her a little, but she felt her womb pushing hard against her abs as her stomach bloated massively, spilling out over Izumi’s huge ass and onto her back as Mei screamed in pure, mind-breaking pleasure.
Ochako loved the sensation of her womb being filled by the hot cum, but as soon as Mei finished dumping it inside, she felt it begin to vanish as her body absorbed it for its own devices. While Ochako’s cock swelled only a little larger, most of the cum was co-opted into her own seed, bloating her balls in seconds. Ochako’s fat nuts hit the ground with a heavy impact, hundreds of pounds of thick, dense cum threatening to crack the concrete floor as they swelled to nearly double the size, each like huge exercise balls inside her sack.
Mei collapsed from the effort, falling out of Ochako’s pussy and onto the ground behind her as Ochako’s thrusting renewed its ferocity, invigorated by the new sensations flowing from her bloated sack. She grabbed firmly onto Izumi’s waist and stood up, supporting the entirety of her thick wife on her rigid cock.
WIth her mighty arms, Ochako began to move Izumi, sliding her up and down her titanic cock like an onahole as she thrust. She pulled Izumi away as her hips pulled back, then slammed both together in a single motion, sawing more dick in and out of Izumi than ever before.
With a mighty effort, the mostly-limp, continuously-orgasming Izumi reached an arm back and grabbed onto Ochako’s wrist, giving it a single squeeze before she lost her grip. Ochako felt the love and devotion in the simple gesture, and it spurred her on to make Izumi feel even better.
Now that she was standing, her balls were no longer touching the floor, but instead swinging dangerously as she clapped her hips into Izumi’s ass more than twice a second. Sweat poured off of her body, filling the room with her over-potent musk, which was leaving even Mei delirious.
Ochako glanced at the clock on the wall. She had been fucking Izumi for an hour straight, although it had felt much shorter. They had missed class, but she didn’t care. She’d tear down the whole of UA with her dick before she neglected Izumi for a moment.
As time passed, her balls became even heavier, swelling with Izumi’s gift. Her arms finally began to feel fatigue, and her cock began to throb impatiently.
Izumi swung her head around, looking exhaustedly up at Ochako. Her voice was quiet, but Ochako could have heard her from a mile away. “I need it.”
That opened the floodgates. Ochako reached an arm up and regripped Izumi around the collarbone, holding her flat against her body as her cock stretched her even wider, bloating for her impending orgasm.
Her massive, thousand-pound balls clenched, pulling themselves up tight to her body as they unleashed. Gallons of seed poured out every second, visibly distending Izumi’s gut just by the force of the orgasm before settling down into the rapidly-growing womb. Faster than ever before, Izumi’s stomach grew bigger than her tits in mere seconds, and in only a few more, it was the size of her body. As the first minute of the orgasm came to an end, Izumi’s stomach touched the ground, even though Ochako was holding her up, sitting on her cock.
The orgasm was so loud, the gushing, glurching salvos of cum felt like it would shake the walls, but Ochako would not and could not stop. In the second minute, Izumi’s stomach was large enough to fit a horse comfortably. In the third minute, a car, and in the fourth minute, a full-sized van.
If anything, Ochako’s balls felt fuller than before as they entered the fifth straight minute of orgasm. She renewed her thrusting, even as she unloaded gallons of thick, heavy cum straight inside Izumi. The sound of cum splattering had become muted, as her cock was totally inundated in the sea of seed, meaning instead there was a low, constant gushing noise. Izumi’s pussy was clenching and spraying her with arousal even still, encouraging Ochako to not stop yet.
Each spurt from her cock felt like heaven, but as it faded, she just became more desperate for the next one. As they reached the tenth straight minute of orgasm, Izumi’s gut had begun to reach the walls of the lab, pushing Mei’s inventions around under the ever-flowing assault. Ochako felt like she had dumped an entire swimming pool of cum into Izumi’s hungry womb, but still she had so much more to give.
As it met the far wall, Izumi’s womb began to expand to the sides, until it reached those walls too. Ochako began to be forced back as Izumi’s gut pushed for more room. Ochako couldn’t have cum this much over a month, and yet her balls were still squeezing more out. She felt Mei scramble up onto her back as Izumi’s body took up more and more of the studio, her gut reaching the ceiling. The weight was causing the concrete floor to crack beneath them, and the far walls began to groan under the orgasm, but after twenty straight minutes of mind-bending orgasm, Ochako finally began to feel relief.
Her balls emptied at last, her firehose turned to a trickle as she fell forward onto Izumi’s body, Mei still on her back. The three lay there in silence beyond heavy breathing for what felt like ages as they recovered. Remarkably, Izumi was still conscious, although she didn’t quite know how. She knew her mind was changed irrevocably; the nearly unending pleasure had rewired it, reshaping her understanding of her place in life.
Ochako had changed as well. She felt more confident, more powerful, and more assertive. After not just experiencing, but causing that force of nature called an orgasm, she felt superhuman. As her arms recovered, she reached forward and grabbed onto Izumi’s face, pulling it gently closer for a kiss.
As Izumi kissed back, they both noticed something: Izumi’s body had begun to process the ocean inside of her. Rapidly, her gut began to shrink, pulling back from the ceiling and walls. Izumi felt infused with energy beyond anything she’d experienced before, like she could run ten marathons, or jump to the moon and back. But that wasn’t all.
Ochako marveled at Izumi’s growing form. Her tits swelled until they each were the size of her entire torso and then some. Her hips grew wider to accommodate Ochako’s fat dick, and her ass grew plumper, the perfect cushion and pillow for Ochako’s pleasure. But still, that wasn’t all.
She marveled as Izumi’s body grew like her own, her legs and arms lengthening as the cum was absorbed. Ochako let her softening dick fall free, and set Izumi down on the ground as the last of her clothes shredded to bits, still supporting her weight so she didn’t fall over. In a few moments, Izumi was able to look Ochako in the eye, but she kept going. As the last of the cum was absorbed, leaving Izumi with a little bit of a soft, squeezable chub left on her stomach, she had to look down at Ochako from her new height of 6’10”.
Her tits were truly massive, the nipples over an inch thick and already begging for Ochako to suck on them. She towered over her master, slowly turning around to look down at her, and Mei on her back. Her hips were wide enough that she’d have trouble walking through most doors, and her ass meant she’d have to buy an entirely new wardrobe. Her thighs were thick and squishable, but still firm and healthy, showing no gap between them despite her flared hips, and Ochako could tell her lips had grown more plump.
Ochako loved her with all her heart before, and now she was somehow more perfect.
Mei was the first one to speak. “Holy shit.”
“Yeah,” Ochako grunted.
Izumi nodded. “I never would have thought…”
Mei scrambled down, trying to ignore her cock, which was rock hard again, thanks to Ochako’s musk filling the entire lab. Just looking at Ochako made her feel stupid.
Ochako scooped up Izumi with ease, despite her new size. She was nearly four hundred pounds of thick, curvaceous woman, but Ochako had carried more than that between her legs. The fat, two foot long flaccid cock hung over her pair of gigantic nuts, but her powerful legs bore everything without complaint.
“I’m going to keep fucking you until you can’t fit in our apartment,” she promised Izumi, leaning in and kissing the gigantic woman. “And then I’m going to keep filling you until you can’t fit in a house.”
Izumi’s heart beat faster, imagining the pleasure that awaited her in the future.
Ochako turned to Mei, looking at her intently. “Mei.”
“Yes?” she replied obediently.
“Two things. One, make another machine like that, but better. I want to be bigger.”
Mei nodded, her imagination running wild.
“And two, you live with us now. I expect you to be there this evening.”
Without another word, she carried Izumi out of the lab, having to carry her sideways, even through the wide, industrial doors.
Mei sat there, her cock twitching needily as the doors closed. She gulped.
“Yes, Master.”