“Oh, Ma-ac!” Trenderhoof sang out. “I’m home!”

He shut the door behind him and waited for the inevitable flood of Apple family members to come rushing at him. When none appeared, he blinked, waited, then shrugged.

“Huh,” he said aloud. “Guess everypony’s out working.” Oh, well. He slung his duffel up over his shoulder, grunting a bit at the weight. At least he could finally put this dang thing down.

How he wished Mac had been able to pick him up at the station—then, at least, he wouldn’t have to carry this darned bag around. If he hadn’t packed it himself, he would’ve sworn it’d been filled with rocks. Mac would have made short work of it, though. It was one of the benefits of having an absolutely stacked stud of a stallion for a coltfriend. Trenderhoof entertained himself by picturing it: Mac, slinging his duffel over his arm, one huge bicep filling the shoulder strap completely, his pecs straining against his shirt as he hefted the bag as easily as carrying a pillow—

Though Mac wasn’t quite that big. Still, it was a sure thing that he’d be able to carry the bag a lot easier than Trend. And still, Trenderhoof told himself, he could dream.

His shoes—bought on sale at the new major departmental store in Fillydelphia; everypony had been talking about them, and he just couldn’t resist trying a pair for himself—clacked against the wooden floor as he made his way down the hall. He turned past the kitchen, then brightened when he saw the door to Mac’s—their—room loom in his vision. It was all he could do to stop himself from squealing in glee.

As he made to open the door, though, the knob clicked loudly—and a familiar, booming voice said, “One mo’—who is it?”

“Mackie!” Trend said. “It’s me! I just got back. Okay if I open the door?”

There was a pause. Then, hesitantly, Mac said, “Anypony else there with you?”

“Nope!” Trend said happily. “Just me.”

“Uh.” Trend couldn’t see him, but he could imagine what Mac was doing right now. From the sound of it, he had on that adorable thinking face of his: brow furrowed, tongue held carefully between his teeth, and his fingers tapping on his lap. On his thick, broad-muscled lap. Trend always loved to sit in it. “C’mon in, I guess.”

But Trend was already pushing open the door. “Oh, I’ve missed you,” he gushed. “You wouldn’t believe how lonely a stallion can get in the big city—even amidst all the adoring crowds. Oh, it’s just so wonderful to be back in the country, back on the farm, back here with—”

He blinked, noticing Big Mac for the first time. His voice went up a little in pitch, and his next word came out as a bit of a squeak. “—you.”

Big Mac just sighed. Then, grinning in that helpless, dorky way of his, he glanced down at Trenderhoof and gave a little wave. “Heya, Trend.”

Glanced down. Big Mac was sitting on the bed, but Trenderhoof was on his feet. Big Mac shouldn’t be able to look down on him like that, unless...unless…

Trenderhoof sucked in a breath as he looked up at Mac...then up, and up, and up. “Hello, Mackie,” he squeaked out.

Big Macintosh had his name for a reason: he was the largest, most well-built stallion in the entirety of Ponyville. At just over six and a half feet, he’d gone his whole life without finding another pony who could come up to higher than his chin. At five feet, nine inches—respectable for a stallion, though certainly not huge—Trend had always come up to just above his shoulder. Now, though, he was beginning to feel a lot smaller.

It wasn’t difficult to tell that Mac looked bigger—a lot bigger, in fact. He was easily six inches taller than usual, Trend estimated, his mouth going dry. His arms were wider, his thighs thicker. His pecs were huge, an enormous pair of wide-set spheres that looked like they could crush steel. Trend wobbled for a moment, slightly unsteadied by the sheer size that his coltfriend was projecting.

That wasn’t the only place Mac had grown, though. He’d sat down on the bed mostly unclothed. Save for a clean white t-shirt and a pair of boxers, he was entirely naked. His huge arms filled out every inch of his sleeves, his bulk straining against the tight fabric. Every one of his clean-cut abs bulged through his t-shirt as if it weren’t even there. And his boxers, Trend realized, swallowing again, weren’t doing much to contain his other size, either.

Big Mac’s stallionhood had always been one of Trend’s favorite parts of his body—alongside his muscles, his height, and his humble, all-country lovable personality. It was, Mac had red-facedly admitted to Trend their first night “together,” one of the main reasons he thought his name particularly fitting. Normally, Mac’s length came “only” to a jaw-dropping fourteen inches, with a pair of testicles each bigger than both of any normal-sized stallion’s put together. Now, though, it seemed as though they’d done some growing of their own, too.

They were huge: seven inches across, easily. Each one was as wide and plump as a fat cantaloupe, and were straining so hard against Mac’s boxers that the fabric had shredded in places. One sniff of the air filled Trend’s lungs with Mac’s familiar musk; instantly, he was home, his own crotch twitching at the scent. The size of his balls and musk, though, were nothing compared to the new size of his python, though.

Mac’s member really brought new meaning to the word “big.” It was almost as thick as Trenderhoof’s waist—which was, admittedly, fairly slender—and had pushed its way through the waistband of Mac’s boxers. At a mind-bending thirty-plus inches—it had to be; there was no way that monster was anything less than two feet—it drew Trend’s eye instantly. It was clamped firmly between Mac’s big, round pecs, the shaft rubbing against the cleavage of his chiseled pecs. A steady stream of precum was drooling down the side; more than half of Mac’s boxers and shirt were already stained dark with leaking pre. By the size of his balls, there was far more where that had come from.

“Holy cow, Mac,” Trend breathed. He could feel his fingers twitching. He hadn’t been paying attention, but he was already hard—beyond that, even, if the throbbing at his crotch was anything to go by. Then again, Mac was far beyond even that. “You’ve been holding out on me?”

Big Mac shot him a strained grin. “Sorry, Trend,” he said. There it was—that adorable, sheepish, irritatingly stubborn “this is all my fault” look of his. “Didn’t mean for you to see me like this. Now, you just shoo, and I’ll get this taken care of.”

Trenderhoof just gaped up at him. “Shoo?” he asked. “Why in all of Equestria would I shoo? From...this?” He gestured wildly at Mac, not sure of which part of his huge body he should be gesturing at.

“Well,” Mac began, “I—”

Trend wasn’t listening. He couldn’t take it anymore. He rushed up and poked at Mac’s thigh—that enormous, beautiful, tree-trunk thigh—while squeezing it with his other hand. A moan escaped Mac’s muzzle, but Trend was too taken with his new toy. “Goodness, Mackie,” he said. “I didn’t know a stallion could have a growth spurt this late in life.”

“I—”

“And—oh, my.” Trend’s hand flew to his mouth. Hesitantly, he reached his hand down over Mac’s monstrous, throbbing stallionhood. Then he threw away all restraint and gave it a gleeful squeeze. “Now this is a real stallion!”

But Mac didn’t have any reply—at least, not any intelligible one. Instead, he groaned, in a mix between pleasure and strain. The fibers of his boxers strained and popped as his body expanded a bit further. Trenderhoof’s eyes nearly popped out of his skull when he saw Mac’s erection getting even longer and thicker. When he glanced up to see Big Mac a good two inches bigger, he very nearly fainted.

“S’not a growth spurt,” Mac bit out. His whole body was erect, trembling as if trying to hold something back. “It’s an Apple stallion thing. I—”

“An Apple thing?” Trenderhoof was beaming. “Oh, goodness—I knew country ponies were big, but never this big! This is just fabulous—incredible—” He saw Big Mac’s gentle, but strained look, and shut himself up. Chuckling awkwardly, Trend quickly said, “Oops. Sorry.”

Macintosh sighed. He relaxed a bit, his big hands resting in his lap. The bulge in his boxers had swollen up so much with the fat orbs within that the edges of the fabric were actually brushing against the knuckles of his big, muscular hands. “Earth ponies naturally got a lot of energy in ‘em. Apple stallions doubly so. If I go too long without takin’ care of things, it builds up. Swells up, and I go up with it.”

“Taking care of things, hm.” Trend mulled that over. Then his jaw dropped. “Mac! Do you really mean to see that in the two weeks I’ve been away, you never once—”

“Nope.” Big Mac shook his head shyly. He looked adorably awkward even at seven-plus feet in height. “Wanted to wait for you, Trend. But it just got so bad, and I just couldn’t hold it back anymore—I was just gonna take care of it today. Real quick-like. It was just awful tough ‘cuz I never got this big before.”

“Never, huh?” Trenderhoof laid a hand on Big Mac’s stomach. It was, ostensibly to comfort him, but Trend couldn’t deny that the feeling of those diamond-hard abs against his palm was a huge turn-on. “Mackie, you know you don’t have to hold out for me. It’s natural. Every stallion ‘takes care of business’ on his own time.”

Big Mac blushed. “Just like makin’ it special,” he mumbled.

“Well, then—good thing I’m here.” Trenderhoof waggled his eyebrows up—and up, and up—at Big Mac. “Because I’ve got to admit, Mac, but seeing you this size is a huge ‘unf’ moment for me.”

Big Mac blinked. “Say what?”

“Oh, come on, Mackie.” Trend gently stroked his fingers along the cleavage between Mac’s ab muscles. So thick! So strong! “You didn’t think that a huge stallion with huge muscles and a huge package wouldn’t have equally huge sex appeal?”

Big Mac’s blush deepened. “I, uh,” he mumbled, staring down at his lap. “I always was kinda embarrassed about it.”

“Embarrassed!” Trend gaped. “Mackie, you’re a stud. The biggest stud I’ve ever seen.” He slid his hand across Mac’s shaft—so warm, so hot—and gleefully noted that he couldn’t wrap his fingers even halfway around. “I’m not ashamed at all to say that you’re turning me right on, sweetie.”

“Really?”

“Oh, yes.” Big Mac’s member throbbed, and Trend shivered in delight. “Oh, the things I would do to you. The things I would let you do to me. A bigger you is a sexier you! I think you should glory in it while you have the chance.”

Big Mac’s face was the brightest red it’d ever been. “Shucks,” he muttered, but there was a spark of interest in that level gaze. His eyes darted toward the open door. Trend’s gaze followed his.

“Well,” Big Mac said slowly. “If y’really are interested...then I ain’t got any intention of turning you down, Trend. I just hope you know what you’re getting into.”

Trenderhoof swung the door shut with a flicker of his horn. “Getting into?” he asked. “Now what do you mean by that?”

Big Mac grinned down at him. “Just mean I ain’t done growin’,” he said gruffly.

“Not...done?” Trend eyed Mac’s huge erection, his impossibly broad torso, and felt his crotch dampen. “How much bigger can you get? And how?”

“A...lot,” Mac admitted. “I’ve broken my bed before. Once it’s all built up, the closer I get to finishin’ off, the bigger and stronger my body gets. Guess that it’s way of pushin’ me over the edge.”

“Not to mention push me over,” Trenderhoof said. In a flash, he had his hand over one of Big Mac’s pecs. It was huge—easily larger than Trend’s entire head—and surprisingly soft, he found. His hand sunk a good inch into the relaxed muscle, squishing Mac’s fur, but when the big stallion inhaled again, his chest flexed, his pecs expanding hugely until they filled Trenderhoof’s vision.

He found Big Mac’s nipple and gave it a squeeze. Big Mac moaned, wheezing as his erection splurted out a generous glob of pre over the floor. A wicked grin crossed Trenderhoof’s muzzle.

“You like it when I touch you, huh, big boy?” he asked. In the blink of an eye, he’d torn his shirt and pants off; in another, he’d all but ripped his briefs away, exposing his own erection. Big Mac was breathing too heavily to properly speak, but there was no doubting the flicker of interest he gave toward Trend’s crotch. Trend smirked. “See what you do to me, you big stud?”

In another blink, he’d slung one leg over Big Mac’s thigh and perched himself atop it. The huge muscle bulged beneath his taint, but Trend’s smile only widened. He rubbed Mac’s pecs, at first softly, then more firmly, molesting the larger stallion’s chest. With a boner throbbing hugely in his shorts, Trend began to pull himself closer to the bottom of Mac’s torso, his taint grinding against Mac’s thick, corded muscle the whole while.

Mac groaned. “Sure—do,” he grunted. He had his hands clenched at his sides, and his eyes were squeezed shut. Trend saw an opening.

A few inches further, and he’d hiked himself up over Mac’s swelling bulge. Trend shifted his weight, letting Mac’s plump nuts squished beneath his own plump rear. He could actually feel them churning, sloshing with seed. The thought of so much virility, so much masculinity tied up into Macintosh’s growing body set his libido on fire. He needed to feel, to experience this specimen, this—this—god. He needed to grind his body over every inch of him.

And he had every intention of doing so.

Groaning slightly, Trend stretched his arms around Big Mac’s torso and hugged him, as hard as he could. He could feel Mac’s thick, hot muscles rippling and twisting against his fur, could feel the rise and fall of the huge stallion’s chest against his forehead. Trend’s hips slowly grinded against the bottom of Mac’s stomach, humping his abs even as Mac’s swelling stallionhood rubbed between Trend’s flanks.

And it was swelling—and noticeably so. Already hard, Mac’s arousal only grew as his whole body got even bigger. A moan escaped Mac’s lips as he inched up further, leaving seven feet behind as he approached the half-foot mark. His boxers ripped further, tearing right down the seams as huge, red splotches of his fur burst their way through. Trend just kept rocking back and forth, eagerly molesting every part of Mac’s body that he could reach as the big stallion went on getting bigger.

Mac groaned as he surged up higher. His bed creaked beneath his massive weight, the mattress swaying uneasily. Though his eyes were closed, his hands were flexing, twitching with what could only be growing arousal. As Trend rubbed himself against Mac’s widening washboard abs, the big stallion’s hands slowly moved over his crotch.

With a huge rip, Big Mac’s boxers just shredded off of him. His hips just burst out of them; his thighs flexed reflexively as fresh air brushed across them. The fabric had already been all but painted on before, but now, his size was undeniable.

Big Mac was panting. His hands instantly clamped firmly around his huge erection. His huge, round pecs bounced and flexed, his chest rising and falling as he frantically jerked himself off. Trend groaned happily when he felt Mac’s huge arms pinning him in from both sides, then squealed happily when Mac’s huge flare poked up against the top of his neck.

“Getting excited, Mackie?” he purred. He slid one arm around Mac’s bicep—it was so huge, so round!—and hugged it to his chest. He could barely fit his arm all the way around.

“Nggh.” Mac grunted. “Maybe.”

“Oh, let’s face it,” Trenderhoof said. He was still grinding his bare crotch against Mac’s abs, though his attention had now turned to the big stallion’s absolutely massive bicep. He rubbed his chest against it, feeling Mac’s long, thick tendons bulging and flexing against his coat as Mac struggled on the brink of absolute lust. “You turn yourself on even more than you turn me on. You love being this big. You love getting huger.”

“M-maybe.” Big Mac’s voice cracked. “I never wanted to—to be bigger than anypony else—to make ‘em think I was trying to be better than ‘em.”

“But you are big,” Trend murmured. He gave Mac’s arm a big hug. It had to be wider than his waist by now. Meanwhile, Mac had grown to pass eight feet by now; if he’d been standing up, Trend would have just barely come up to his nipples! His big, hard, erect nipples. Trend found his mouth watering at the thought. “And it’s the hottest thing I’ve seen in years. You should be proud of how big you are—of how big you can get.”

Mac groaned again. A huge splurt of his pre burst against the back of Trend’s chest, and the smaller stallion groaned. “I—I do,” he admitted, biting his lip. “I ain’t told anypony, though. I’m scared, sometimes, of just how big ‘n strong I am, but it turns me on somethin’ fierce when I see a tall stallion like you only come up to my shoulder. And when I get to growin’ like this...it just makes the problem worse.”

“Worse?” Trend asked. “Or better?”

Big Mac shuddered as Trend’s bare flanks clenched around his base. “I—it does feel awful good.”

“It feels good to feel you feeling good,” Trend said. He chuckled. He gave Mac’s stomach another hump, and gave his pecs another squeeze. “Think you can get any bigger for me, sexy?”

In response, Mac just groaned. The bed creaked beneath his weight as his body inched up further. All the lust, all the energy, all the power of his libido were building up inside of him, straining against the ripples of his huge, muscular body. Trend felt his erection throbbing even harder as he watched Mac’s huge head approaching the ceiling. He was only a few feet away now—and sitting down! He had to be at least nine feet standing; if he’d been on his feet, there was no doubt that his head would have been rubbing against the ceiling.

Something twitched in the corner of Trenderhoof’s vision. Turning himself in a semicircle, he came eye-to-shaft with Big Mac’s huge, throbbing stallionhood. “Well, hello there,” he purred. “You look like you’re looking for a good time.”

Rivers of precum were running down the sides of Mac’s magnificent slab of meat; it was tall enough to poke past Mac’s pecs, and thicker around than Trenderhoof’s waist. Licking his lips, Trend reached out and hugged it, embracing Mac’s member and squeezing his hands around it. They could just barely meet around the other side.

“O-oh, Trend,” Mac groaned. “I’m—I’m so big. So full.”

“That you are,” Trend murmured. He eyed Mac’s huge nuts. Each one had grown to the size of a beanbag chair by now, and were dropping far past his knees. He was able to rest his feet on them, his toes wiggling as they sank a bit against those enormous, plush nuts. Another spurt of pre spattered over the top of his mane, and he licked his lips hungrily.

Heaving his body forward, Trend began to hump Mac’s stallionhood, squeezing it between his arms and pleasuring it with his whole torso. Mac groaned, squirming beneath and above him, his body swelling even larger by the second.

There came a mighty groan—then a cracking, then a violent crash! as the bed broke beneath them. Big Mac’s body was just too huge, too heavy, for it to hold up any longer. With Mac’s current size, though, the drop down wasn’t even far, and the huge stallion’s big, muscular flank absorbed most of the impact. Trend was too occupied with his new prize to notice, anyway, too busy lapping at Mac’s precum and humping his shaft to do anything other than moan.

“Mackie,” Trend moaned. “You’re so big.” Mac’s shaft was rapidly reaching his own size; as Macintosh began to lean back to avoid breaking through the ceiling, Trend found himself clenching the bottom half of the gigantic member between his thighs as he rubbed his chest against the flare. “Oh goodness Mac, you’re filling up the whole room.”

“Trend,” Big Mac gasped. “I’m—I’m gettin’ close now.”

“Getting close to filling every inch of your bedroom, you mean.” Trenderhoof groaned as he ground his own cock against Big Mac’s pony-sized meat. A bubble of pre burst from his own, much smaller shaft, bursting against Mac’s. Behind him, he could hear Big Mac’s body groaning, creaking, bones lengthening and muscles bulging as his whole body grew to ever-more glorious sizes. “Keep growing for me, big boy. We’re going all the way with this.”

If Big Mac’s increasingly labored breathing was anything to go by, he was already most of the way there. He’d been forced back onto his back, his feet creeping toward the other end of the room as he grew. His expanding body pushed all of his furniture—a desk, a dresser, a wardrobe—off toward the walls, toppling some, and breaking others. When he grunted, massaging his own massive, cum-filled nuts, he actually surged outward another foot in height. He was nearing three times Trend’s size now, his cock reaching more than halfway to the ceiling.

Trend felt his own pleasure growing, a tightness building at the base of his crotch. With every hump, he watched Big Mac’s shaft tower above him, his coltfriend’s very stallionhood outgrowing him. The realization that he was no bigger than even Mac’s shaft—that his balls might even be taller than he was soon—just made him hump all the harder, the lube of Mac’s pre letting him slide his shaft against Mac’s with a hot, easy schlick-schlick sliding motion.

“You’re huge, Mac,” Trend groaned. “So huge. Getting bigger and bigger and—grah!”

His hips bucked wildly as he went over the edge. He slammed his erection against Mac’s huge meat again and again, grinding his spasming cock against Mac’s tree-trunk member with every spurt of cum. Trend felt like he was cumming buckets, each rope of his load nearly twice the size of his normal orgasms. Big Mac’s musk, his presence, his size was overpowering, clouding his mind with the sheer evidence of his sheer power and sexuality.

By the time he came out of it, Trend was panting. But there was still one other stallion who hadn’t finished yet.

Big Mac snorted, whinnied, groaned. His deep, rich voice filled the room. The floor rumbled with the strength of his arousal, the power of his swelling body. He more than filled the room: he dominated it, every inch with his massive, growing form.

He didn’t speak—he didn’t need to. Instead, his moans suddenly intensified, his breaths becoming sharper and shorter until finally, his cock bulging and spasming with strain, he reached his peak.

Mac threw his head back, shattering the plaster of his wall. His huge feet pushed forward, shoving against the opposite wall. Trenderhoof struggled to hold on as Mac’s shaft bulged, swelling wider and wider before him, until it was impossible to hold on any further.

Mac’s orgasm hit him like a freight train, his whole body lurching with the force of his peak. Huge globs of spunk, each one gallons in volume, volleyed into the air and either splattered on the ceiling or the floor. His balls churned and groaned, their contents sloshing as more and more jizz burst from his cock and into the air. Trend swallowed as much of it as he could as it fell, his mane, face, and entire body getting drenched with Mac’s jizz as his cock erupted like a volcano.

When he finally finished, Big Mac groaned. The floor creaked and complained beneath his massive weight—he had to be more than fifteen feet tall by now, and at least a tonne of mass. Sucking in a long, slow breath, Mac shifted his weight before opening his eyes up again.

Trend groaned too. The bucking of Mac’s cock had thrown him backward, sending him toppling onto Mac’s cum-splattered chest. Trend’s groan was softer, escaping him as he reached up to adjust his glasses. Unsteadily, he pushed himself into a better position—and paused when he felt his fingers sink into the warm flesh of Mac’s pecs.

Then he grunted. Something heavy had pulled him forward, crashing against the small of his back and forcing him to the muscled, red-furred “ground.” Trend let out an “oof,” then blinked rapidly up at Mac’s grinning face.

“You liked that,” Trend said, grinning back. “Didn’t you?”

Mac chuckled. He was only blushing slightly this time. Admittedly, it was kind of difficult to be flustered after you’d covered a room in your spunk. “Eeyup.”

Trend grunted, trying to push himself to his knees. No good. Mac’s forearm weighed heavily on his back, holding him against the big stallion’s soft chest. “You wouldn’t have any plans of letting me go anytime soon, would you?”

Mac’s eyes had slid closed again, but one poked open to stare down at him. Mac was smirking. ”‘Nope.”

Trend made a half-hearted attempt to struggle. Held in place by a hand wider than his torso, though, it was clear that he was going nowhere fast. “Not that I’d want to escape,” he mumbled, a smile curving his muzzle. “How long are you going to stay this big?”

“A little while,” Mac said simply.

“Good.” Trend snuggled against Mac’s pec, feeling the rise and fall of his chest as it flexed and bulged beneath him. “Means I get to keep all this for a little while longer.”