Work that day was, to start with, uneventful. Pipsqueak had Mondays off, but today he was back on duty at the Shake Shack, mixing up protein powders and banana smoothies alike for the thirsty Ponyville clientele.

It was an easy enough job, he guessed. All he had to do was stand behind a counter, take orders, and then fix up drinks. Anypony could do that. And at least his baggy uniform—the manager hadn’t had any small enough for him when he’d started two months ago—covered up most of his twig-thick arms.

Pipsqueak forced a smile onto his face as he took down an order for a Strawberry Special. The mid-morning rush was pretty big today. It didn’t hurt business that the Shack was right next door to the Ponyville gym. More than one stallion decided to come over for some refreshment in between workouts. Every one of them came sweaty and buff from working out, their muscles rippling under their skin. Every single one of them was taller than he was.

As he worked, Pip couldn’t keep his eyes off of their biceps, their bulging pectoral shelves, the bulges at their crotches. He couldn’t help himself. Usually, they made him feel inadequate, tiny, worthless. But today, he envisioned himself wearing those muscles, bearing that tall, stocky frame with a smirk on his face and a spring in his step. I’m going to be you, he promised silently. If not today, then someday soon.

Rumble never had to feel inadequate at his job. He worked as an assistant at Quills and Sofas, lifting heavy furniture with ease and always happy to strike a few poses for an interested customer. Pip had seen his thick, veined biceps straining against his too-tight polo uniform more than enough times. He couldn’t help but entertain a brief fantasy of a smaller Rumble, panting beneath a too-heavy sofa as a larger Pipsqueak lifted the one next to it with ease.

“Hey!” the mare at the grunt of the line yelped. “You gonna take our orders or what?”

Rumble jumped. He quickly got back to work. This time, though, he had a fist clenched around the amulet hanging around his neck.

Getting Rumble to wear it had been easy enough. The taller stallion, though very much not effeminate, had a thing for flashy stuff. Rings, fancy watches, ear studs—he hadn’t even thought twice about accepting Pip’s antique “gift.” It might have been his imagination, but as he clutched the amulet in his palm, Pip thought he felt a rush of warmth spreading through his body.

As he worked through his shift, the sun getting higher and eventually descending in the sky, he imagined—or was it felt?—his clothes getting a little bit tighter around him. He got a boner watching a particular studly stallion striking a few most-muscular poses for an eager mare, and jerked it off in a stall over his lunch break.

He was disappointed when he found that his stallionhood looked to be just the same puny size as ever, but he came to the mental image of him having that stallion’s muscles all the same. And when he finished, he could have sworn to himself that his flaccid dick looked just a tiny bit longer than usual.

The second his shift ended, Pipsqueak rushed home. He slammed the door shut behind him, trampled up to his room, and seized a measuring tape and pencil from his bedside table.

He marked his height right above his forehead and compared it to a mark he’d made just that morning on the wall. When he turned to inspect it, he almost shouted with glee. The new mark was a whole inch higher on the wall than the previous one.

He double and triple-checked it, but all that did was confirm it. Pipsqueak, the tiny little stallion, had grown a whole inch taller in under twelve hours. He took a deep breath. This time, he didn’t imagine feeling his inflating chest push a bit harder against his shirt—he knew it was happening. He flexed an arm, and nearly giggled when he saw a bit of a bicep bulging against his palm. He had definition! Not much, but it was something!

Five-foot-six wasn’t that much different from five-foot-five. But when Rumble arrived home, tuckered out from a long day at work and the gym, Pipsqueak silently pumped a fist. The other stallion was still taller than he was, but the difference was—to him, anyway—noticeably lesser. His head actually reached Rumble’s shoulder now! Sure, there was a long way to go, but this was definite proof that the amulet worked.

"Man," Rumble said, grunting. He flung his bag off to the side and flopped down on the couch. "What a day."

Pip's ears perked up. "Oh?" he said. "I'm sorry to hear. What went wrong?"

"Nothing specific," Rumble said. "Just felt a little bit off. Couldn't even get through my full workout after work, so I just gave up and went home." He eyed his arm—which still had no shortage of muscle on it—with a bit of disgust, and flexed it a few times. "Guess we all just have off days sometimes, huh?"

"Oh, yes," Pip said. "That's a real shame."

"Yeah." Rumble stretched out to his full length—with Pip shrewdly noting his lost inch in height—and yawned. "I'm just tired, I guess. Especially after last night."

"How'd it go?" Pip asked.

"Meh. She was good, but only managed three loads. I was feeling pent-up at work all day."

Only three loads. Pipsqueak's cheeks flushed, and he turned away so Rumble wouldn't see. Fortunately, the larger stallion looked more interested in massaging his foot and staring off into space.

Three loads. He'd seen Rumble's loads before; each one was easily a pint in size. He'd seen mares walking out bowlegged in the mornings, their stomachs bulging with over a gallon of Rumble's seed. Meanwhile, poor little Pip could only manage a few pathetic spurts. His lip curled.

Something the vendor had said yesterday echoed in his mind. Pipsqueak glanced to the side, caught the faint glimmer of gold beneath Rumble's shirt collar. He chose his next words carefully. "That can't be fun. You haven't had a chance to, ah, release yet?"

"Nah," Rumble said. He gave Pip a meaningful look, smirked. "Why? You wanna help?"

"Oh, ah, if you'd like me to." Pipsqueak silently cheered. Rumble was—or at least declared he was—as straight as they came, but he'd never had a problem with letting Pip give him the occasional handy, or even a blow 'n go when he needed release and there weren't any mares around. He'd mentioned in passing, too, how much it turned him on to see how much bigger than the other stallion. Pip had once loved that insult, had savored his smallness...but now all he wanted to do was to turn that around on its head.

Rumble settled back and closed his eyes as Pip took a seat on the couch next to him. With a nervous grin, Pip reached for Rumble's jeans. Rumble winked and moved his hands away. He gave a long, low sigh as Pipsqueak unzipped his fly and let his monster push free.

No matter how many times he saw it, Pipsqueak was always awestruck by the size of Rumble's tool. At near two feet in length, his shaft was a throbbing testament to his masculinity. The second it bobbed up in front of him, smacking lightly against Rumble's pecs, a thick, musky scent filled the air. Pipsqueak felt his own boner chubbing up in his pants, and rubbed it softly as his other hoof brushed across Rumble's.

At first, Pip had been a bit hesitant to start. He remembered what the vendor had said, sure, but he still wasn't sure if he wanted to go all in on this. But from the second his skin touched Rumble's, he was sure. He felt a zap beneath his fingers—and Rumble, accordingly, grunted and flinched away.

"Sorry, sorry," Pip said quickly. "Static electricity."

Rumble rolled his eyes. "What'd you do, roll in a carpet or something?" he asked. But he let Pip reach back over to his cock.

And what a cock it was. Pipsqueak moistened his lips as he reached over with his other hand, just barely managing to wrap both all the way around. It was a tight stretch, though; he was just barely able to get it so that his fingernails were brushing against each other. Adjusting himself so that he was sitting on his knees, Pipsqueak clenched his palms together and slowly moved them down Rumble's shaft.

"Man," Rumble mumbled. "Y'know, I'm straight as hell"—Pip "knew" that very well—"but none of those mares ever give half as good a handy as you do."

Pip smirked inwardly. He was getting into this. Rumble's shaft was rigid, achingly stiff between his hands. He could feel it throbbing, swelling, pulsing against his palms. Every time his hands moved up or down, they passed over the larger stallion's massive medial ring, which pushed them apart completely. Rumble would have had difficulty holding his dick in one hand; Pip was certainly having enough trouble holding it in two.

But he knew that that was what turned Rumble on, more than anything. Already, copious amounts of pre were streaming from the larger stallion's cock, lubricating the shaft for more pumping action. Pipsqueak bit down on his lip as he eyed the huge, thick veins running along Rumble's cock.

He could feel it: a warmth, starting from his palms and fingers, and running forth to encompass his whole body. He could almost feel the amulet heating up against his chest as it sapped energy from Rumble's body into his. He could feel his muscles flexing, tightening, growing; could feel his spine lengthening; could feel his boner throbbing against his crotch as it grew.

Because he was growing, alright. He couldn't see anything for sure, but he felt it in his core. "Gosh," he said. "Rumble, I can never get over how big your dick is."

A grin curled Rumble's mouth. "You say that every time, Pipsqueak."

"Doesn't make it any less true."

"Nah," Rumble said, sighing happily. "It doesn't." He gave a pleasurable-sounding grunt as Pip's skillful fingers wrapped around his knob, his other hand softly massaging Rumble's balls.

"Fuck," Rumble said. "I just love being this big, y'know? I'd bet there's not a stallion in town as big as me. Except for maybe Macintosh," he added. He smirked. "Even 'big bro' Thunderlane has nothing on this." He flexed his biceps and chuckled when he saw them bulge out almost as big as his head.

But not as big. Because Pip could feel his own arms thickening, beginning to ripple with muscle as he worked Rumble's dick over. The warmth spread throughout his body. He was really feeling it now. He'd felt it all throughout the day, but now...it felt focused. Concentrated. Bigger, he told himself. Bigger, and bigger, and bigger, until you're not so small anymore. Until you're looking down at Rumble instead of looking up.

"And you're just so small," Rumble said. One of his hands absentmindedly draped itself over Pip's shoulder before moving down to give his rump a squeeze. Pip blinked, and Rumble chuckled. "Even the mares I date have more muscular asses than that. No offense," he added quickly.

"None taken," Pipsqueak said. Of course, his reason for doing so wasn't quite what Rumble imagined. He watched Rumble flexing, and saw his own arm growing thicker. He pumped Rumble's cock, and realized that it looked a bit smaller than he remembered; suddenly, the tightness in his crotch felt much tighter than he'd ever felt before, almost impossibly so. His heart skipped a beat when he looked at Rumble and realized that, though the other stallion hadn't slumped at all, he was looking down on him a little less. Or perhaps Pip was looking up a little less.

"In fact," Pip grunted, really getting into the handjob. Rumble groaned softly, his muscular thighs tensing as he prepared for release. "I just love it."

Rumble let out a soft cry as his hips jerked into the air. Spurt after spurt of thick, creamy cum erupted from his throbbing cock. Gobs of his spooge spurted out into the air. Pip watched it all, carefully. He'd seen Rumble cum before. He'd seen how much jizz he could put out when he was pent up. But this looked like barely three-fourths of that.

And suddenly, Rumble's stallionhood looked a lot less impressive. The other stallion might take it for going flaccid. But Pip knew the truth.

Rumble melted into the couch's pillows. "Man," he grunted. "That was good. You mind cleaning up?" He gestured toward the stained carpet.

"Oh, no," Pip said. "Not at all."

"Good." Rumble slapped his thighs, then stood up. His softening cock leaned against the inside of his thigh, his big nuts dangling below it. He stretched, then yawned again as Pip got to his feet beside him. "I think I'm gonna turn in early."

Pip's heart skipped a beat as he pulled himself up. His clothes felt tight—much tighter than when he'd come home. Dare he hope...?

But he didn’t have to. Where the top of Pipsqueak’s head hadn’t even reached Rumble’s shoulder before, now Pip’s eyes were level with the bottom of Rumble’s chin. Pipsqueak ran a quick calculation in his head. He must have grown at least two inches—and Rumble, then, must have shrunk down a corresponding amount.

And his clothes did look baggier than before. But Rumble didn’t notice. Instead, the formerly six-foot-six stallion (now barely six-foot-three) yawned again and gave Pip a thumbs up. “Thanks again, Pip. You have a good night.”

Now standing at a proud five-foot seven, pushing five-foot-eight, Pip gave Rumble a nervous smile. “You too,” he said.

The instant he heard Rumble’s door close, Pipsqueak all but tore his pants off. His own erection was throbbing harder than he’d ever felt it throb before. He almost gasped when he saw how big it was. A pilfered ruler from the kitchen proved his suspicions: “Little Pipsqueak” was now a good eight inches in size.

“Fuck,” Pip muttered. He was already stroking his dick madly, trying to remember how big Rumble’s dick had been. He’d started at eighteen inches...but four inches later, he’d be down to fourteen. Just barely over a foot.

“And not bigger for long,” Pip mumbled, closing his eyes. His cock completely filled his hand; his balls, for the first time in his life, felt heavy with their seed. He kept stroking, even as his other hand explored his new body: his thicker pecs, his noticeable biceps, his tighter, round bubble butt—

With a muffled gasp, Pip felt his orgasm seize him. He rode it out, his hips bucking wildly over the carpet as his growing nuts tried to empty out what felt like every bit of spooge they’d ever produced in his lifetime. When he’d finally finished, he let out a long, shuddering sigh and opened his eyes.

The puddle on the carpet from his orgasm wasn’t just a few measly bits of string. Instead—Rumble felt a certain amount of pride growing in his chest—there had to be a solid cupful down there. Maybe more. It wasn’t near the size of Rumble’s monster orgasm, but it was close. Half the size, maybe. And it was going to get a heck of a lot bigger.

He didn’t mind cleaning the carpet. Not really, when every stroke of the fabric cleaner reminded him of how much bigger, how much more virile, how much more masculine he was getting. That night, he turned into bed with a happy smile on his face, his body still growing as he slept. On the other side of his wall, Rumble slumbered, too, his body steadily growing smaller in his increasingly baggy clothes with every rise and fall of his chest.

Next Chapter: Chapter Three: The New "You" Estimated time remaining: 27 Minutes