Bigger Little Brother

Shining Armor stared, wide-eyed, as his brother began to expand before his very eyes. Before this, all he’d seen was the evidence, the aftereffects of Dusk’s burgeoning height. But now, the transformation was occurring right in front of him.

Dusk’s head pushed up against the wall, the plaster cracking as he leaned his increasing weight against it. His legs lengthened, going from long to huge, his thighs thickening with bulging, corded muscle as they pushed his hooves across the room. His hoof bumped against the foot of Shining’s Armor’s bed and then kept going. His massive leg slid under the mattress before upending the entire piece of furniture. The poor bed found itself pushed off of the ground and then squeezed against the wall by the giant colt's growing hoof.

Shining’s breath quickened in his chest. Dusk was filling up the room—and fast. It seemed like all of the growth of the last few days had decided to stage an all-at-once encore. In what seemed like no time at all, Dusk’s horn was rubbing against the ceiling, his flanks nearly filling the space between Shining’s closet and the far wall. His hooves were almost touching the opposite side of the room.

Dusk’s scent, his heavy, overwhelming musk, was all Shining could smell. His labored grunts and high-pitched moans were all he could hear. And soon, as Dusk grew and grew and grew, he found that Dusk was all he could see as well, a swelling mass of purple that was coming to fill every cubic inch of space Shining’s room could offer.

And his cock—Shining blinked lazily up at it as it swelled with the rest of him, then yelped as Dusk’s stallionhood began to grow towards him. Its expanding underside rubbed against the rough carpet, further stimulating his giant little brother as it grew. The sensation only seemed to push Dusk to further heights, not to mention what it did to his arousal. Shining found himself pressed against the wall, with nowhere to go—then let out an oof as he felt Dusk’s cock slipping under him. The now pony-sized flare had pushed half of him up into the air, pinning the other half against the wall.

Shining’s ears twitched, picking up a new sound. Was Dusk...whimpering?

“Shining,” Dusk mumbled. “Oh, Shining it’s so hard—I just came and it’s still so hard. What do I do?”

Shining was just barely able to peek over the top of Dusk’s massive flare at his face. When he saw Dusk’s face, he paled. Dusk’s pupils were dilated, more sweat beading on his forehead as his chest heaved up and down. His brother’s head alone was more than half as big as he was; every time Dusk so much as twitched, the entire house groaned beneath the weight of his growing body.

“I—it’s okay,” Shining assured him. Crap, crap, crap. He didn’t think that Dusk would get this big. Sexy fun was one thing, even if it was with his brother. Bringing down the house was another thing entirely. “It’ll be fine, Dusk. Just—don’t do anything rash, okay?”

Dusk didn’t seem to hear him. “Shining,” he whined. He shifted his torso; his head scraped along the ceiling, his hooves pushing out against the walls. Huge cracks spiderwebbed across the room, the ceiling almost cracking beneath the force of his massive horn. His tongue hanging out of his mouth, Dusk panted, “Shining, I can’t reach. It’s just so big and your room is so small.”

“It’s okay,” Shining said again. More and more pre was pouring out of Dusk’s cock, splattering against his stomach and leaving him completely wet. He did his best to rub Dusk’s flare a bit; he could barely even reach his hooves all the way around the head, but Dusk moaned when Shining’s tiny hooves made contact all the same. It was more than a bit awkward trying to jerk his giant brother off while he himself was pinned against the wall by Dusk’s dick, but Shining gave it his best effort.

But it wasn’t enough. Dusk’s shaft flared even wider, a massive glob of his salty precum bursting all over Shining’s belly. “It’s not enough,” Dusk panted, his eyes wide. “It’s not enough. I need—I need—I need.”

He glanced down at Shining, and his pupils contracted. When next he spoke, it was almost like a whisper.

“—You,” Dusk mumbled.

Shining did his best to grin up at him. He kept rubbing, humping Dusk’s flare. All the same, he was getting a bad feeling about the look in Dusk’s eyes. “You’ve got me, right? I’m doing all I can.”

“No,” Dusk mumbled. “I need—I need you. I need to be inside you.”

Shining’s eyes shot wide open. “Uh, buddy?” he said. “Dusk? I don’t think that’s going to work. I really don’t think that’s going to work at all.”

“S’okay,” Dusk said. He seemed to be in a trance. He swallowed, his horn beginning to glimmer brilliantly as eddies of magical power swirled around it. “I—I know a spell.”

“Dusk,” Shining said. But by then it was too late. Dusk’s magic had already picked him up, sliding out from behind his enormous shaft. He dangled before his giant brother, who was panting steadily. “Think about this.”

“Really!” Dusk said. His eyes were wild. “I—it won’t hurt. At all. I’ve tried it before, honest.”

Shining eyed Dusk’s enormous tool skeptically. He’d tried some...kinkier things with Cadance before, but never anything as big as that. It was wider than he was! What Dusk was proposing was nothing short of impossible!

And yet...he had faith in Dusk’s magic, if nothing else. And his brother really did look desperate. His stallionhood was all but gushing pre, a puddle the size of Shining’s bed spreading across the carpet as the floor creaked and groaned beneath Dusk’s pony-sized nuts. And he had to admit...pondering the size of the things that his once-innocent little brother may have taken with this “spell” of his was beginning to turn him on even more. Swallowing, Shining glanced down at Dusk’s shaft one final time before making up his mind.

“O-okay,” he said, somewhat shakily. He licked his lips, feeling his own erection throb. How could that still not have gone away? “But if it starts to hurt—”

“I’ll stop,” Dusk said. “Immediately.” He nodded, and for a moment the overpowering lust left his eyes. But then the lucidity, the sobriety flickered, and his pupils were dilated with need and arousal once more.

Shining considered that. “Okay,” he finally said. “Just—bwuh!”

The glow around Dusk’s horn intensified in magnitude for a second. Shining found himself abruptly turning, spinning with his head over his hooves, as Dusk telekinetically moved him into place. Then sparks started shooting from Dusk’s horn.

Shining’s eyes widened. He glanced down between his legs, wanting to squirm, wanting to feel what was going on down there, but Dusk’s magic held him tightly in place.

Something warm brushed against his flank, and he almost moaned. Dusk’s magic was so...warm, so intimate, brushing against his every hidden place. Then his eyes snapped back open when he felt Dusk’s magic entering him. He felt his legs go slack, his hooves trembling as a strange warmth spread through his lower body.

“Did—did you cast it?” Shining slurred. “Are you ready?” He felt lost in a sea of arousal, his other thoughts muffled by the strength of Dusk’s presence. Dusk didn’t reply at first, opting instead of just push his “little” brother through the air until he was just over the head of his cock.

Shining eyed the throbbing, massive cock with no small amount of trepidation. Suddenly, he was a bit unsure about the whole thing. “Are—are you sure that it’ll fit?”

“It will.” Dusk grunted again. Shining watched as a fat glob of pre the size of his head bubbled from his brother’s tip, splattering all over the floor. “I promise.”

At least he sounded earnest.

Shining took a deep breath. “Okay,” he said, steadying himself. He had to trust Dusk. He wanted to help Dusk feel good. And, deep down, he had to admit that the idea of fitting something that huge inside of him—something that huge, and belonging to his brother—was one of the hottest things he’d ever conceived of. “You can put it in now.”

Dusk levitated him down, and thrust his shaft upward. When Shining felt his brother’s enormous rod prodding hopefully against his tight, muscular flanks, a thought occurred to him: Dusk would be less putting it in Shining than putting Shining on himself.

And then Dusk started pushing, and Shining started howling.

It wasn’t that he was in pain—some part of him had expected to be, magic or no, but Dusk’s spell had done its work. He felt nothing at first, save for the most bizarre sensation of stretching. His stallionhood was throbbing harder than before, which contributed partially; the sensation was both incredibly alien and incredibly erotic. Shining squirmed, panting, his chest heaving as he felt Dusk spreading him wide around his flare.

Dusk stopped immediately. A tremor returned to his voice, a flicker of lucidity. “Sh-shining?” he stammered. “Should I stop?”

Shining inhaled deeply, his mane matted with sweat. “No,” he gasped. “It feels—it feels good. Keep going.” He felt Dusk twitch inside of him—or rather, twitch his whole lower body, his brother’s massive flare setting his whole body squirming with each thrum of blood through its length.

“Okay,” Dusk said. “Just—tell me if you want me to stop.”

Shining took another breath. Then, feeling his brother’s magical grip on him loosen, he turned back to face him. Shining was grinning like a madpony.

“Don’t stop until it’s all the way in,” he said. “You hear me?”

“Shining—”

“What are you waiting for?” Shining hollered. “Shove it in!”

And Dusk did.

Shining howled even louder, his brother’s girth stretching him impossible amounts. It’d been ludicrous—insane—to think that a cock the width of his entire torso could fit into his ass, but somehow Dusk was managing it. Shining writhed, wailing, grunting, and wheezing in pleasure as inch after inch, then foot after foot of Dusk’s stallionhood entered him.

Soon enough, Shining saw something poking up on the bottom edge of his vision. Glancing down, he saw his stomach actually beginning to bulge out. A full foot of Dusk’s length slipped inside of Shining’s ass, and both brothers moaned together. Shining had both his hooves on his stomach, massaging it, feeling the curve of Dusk’s gigantic flare beneath his coat.

“Nngh,” Dusk groaned. “You’re so tight.”

Shining nearly choked. “Says the stallion using me as a cocksock.”

Shining could barely even turn his head at this point—the bulge in his belly had to be a good foot tall by now—but he could imagine the exhausted grin on his brother’s face when Dusk replied, “Yeah, but you like that.”

“And you don’t like me tight?” Shining clenched his flanks a few times, flexing his cheeks around Dusk’s massive girth. It didn’t do much, considering Dusk’s sheer size, but it was the thought that counted. Instantly, Dusk groaned, the churning in his balls actually becoming audible as a huge geyser of precum burst inside of Shining’s stomach. Shining grunted, his hooves pressing into his middle as he felt it bloat outward with the sheer volume that Dusk was pumping into him. He wasn’t even cumming yet.

Dusk just pushing himself in. It felt like his shaft would never end—and Shining never wanted it to end, besides. He goggled when he saw the bulge in his stomach pushing far above him. He grunted, pressing around his middle as he felt his stomach softening around the sides of Dusk’s shaft. It was plumping up with what had to be bucketfuls of pre. Shining gasped for air, coughing as he felt his once-little brother turn him—his entire body—into nothing more than a covering for his cock.

And he loved it. He’d never been harder in his life.

“I love you tight,” Dusk corrected him, grunting between every word. He thrust his hips forward, at least as much as he dared without shattering the floor beneath his weight. “I love feeling how big I am inside you. Oh, gosh, Shining, I can see my shaft inside you.”

Shining grunted, squinting up at the monstrous shaft poking up above—up through—him. He patted it, then moaned, his whole body spasming as Dusk pumped his hips a few inches forward. “That you can, lil’ bro,” he mumbled, feeling his belly squish as more and more precum gushed into him. “That you can.”

The room was too cramped—or Dusk too big—for Shining to actually received a proper rutting. So, instead, Dusk merely took hold of him with his magic and began to pump Shining’s smaller body up and down his shaft, squeezing him around his girth.

Was it him, or did Dusk feel a little...bigger inside of him than he had a second ago? Shining glanced down. He could actually see Dusk’s hooves stretching across the floor, could hear his head scraping against the ceiling as he grew to fill it even more completely. Dusk was growing around him, beneath him, inside of him. He wasn’t anywhere near done growing—not even close.

Shining moaned, his own erection spurting a generous—for him—amount of precum down onto the floor. “Oh, fuck,” he moaned, squirming as Dusk filled him up. “Oh, fuck.” He loved this feeling: being taken, being used. He was nothing more than a toy to cover Dusk’s cock so that his massive little brother could pleasure himself. He’d never been more turned on in his life.

Dusk was panting harder now. The amount of pre pouring into Shining redoubled in volume, rounding out his belly considerably. “Shining,” he gasped. “I’m gonna—I’m gonna cum.”

“Do it,” Shining gasped, his voice hoarse. “Dusk, I want you to cum inside me. I want you to blow your load inside me until I can’t even walk. I want you to fill me up with your damned giant orgasm, every last damn drop.”

That was all it took to set Dusk off.

Shining’s eyes bulged as Dusk’s flare swelled impossibly wide inside of him. He howled, stretched past even his previous limit, and moaned in absolute pleasure as the first flood of Dusk’s seed gushed into him. The first spurt alone outmatched his entire production of pre before; soon, Shining found himself moaning even louder as Dusk’s monstrous orgasm filled him past any reasonable fantasy.

It came flooding into him, each contraction of Dusk’s shaft forcing Shining further down, filling him up and stretching him until he could barely move. Dusk was crying out, his massive balls pumping a veritable ocean of cum into Shining’s gut. Shining kept howling, beating his back hooves against Dusk’s enormous member as it filled him to bursting.

Warm, hot spunk filled his belly, each new bulge of jizz stretching his ass even wider than it had been before. Before long, the amount of cum inside of him had stretched his stomach enough to compete with Dusk’s cock in size; just two massive spurts later, and Shining’s stomach was an enormous, round sphere full of cum.

He coughed, then blinked. He tasted jizz on his tongue—and not just any seed, but Dusk’s seed. But how was that possible? He hadn’t given him a blowjob. He’d never even—

Dusk’s stallionhood erupted inside of him again and Shining coughed up a fat wad of Dusk’s cum. It landed on his belly, splattering against his coat, and matting the fur there even further with Dusk’s hot, sticky load.

He’d never felt so full. Even with Dusk filling him, there had still been some element of individuality, of separation. But now, with Dusk’s spunk ballooning his belly out, Shining was having trouble even seeing himself as something separate from his brother’s orgasm. He was filled, every inch, every drop, with his brother’s seed.

It was almost too much, though. Shining’s gut was stretched wide, impossibly wide, by Dusk’s load. He could feel his belly churning, sloshing as it expanded far beyond any rational size. He felt so tight, the skin over his gut pulled so taut as it struggled to hold in its colossal meal. He felt like he was about ready to burst, as though Dusk’s cum was just too much for him to hold inside of him.

Two things immediately happened. One: Dusk’s cock bulged even wider inside of Shining’s rear. Two: Dusk finally broke through the roof of the house.

It was hard to say which happened first—to both stallions, the entire scene was just a blur of overwhelming pleasure. All Shining Armor knew, though, was that one moment he had been speared on the end of Dusk’s flare, and the next, he was shooting through the air, exploding off of Dusk as the pressure inside of him finally became too much to allow any more cum to enter.

But he didn’t hit the ceiling. He didn’t hit the roof, either. Dusk was too busy growing right throw it. The giant stallion’s moans redoubled as the ceiling crumbled around his burgeoning body. The abused plaster finally cracked, his head shooting right up past the second floor ceiling and up through the attic. Dusk gasped as his head exploded above the roof of the house, greedily gulping down huge amounts of fresh air.

All that size, all that weight, all that growth proved too much for their poor house. It may not have been one of the more fragile apartment buildings of Lower Canterlot, but even the Velvet household could only stand so much abuse. Dusk’s now several-ton weight collapsed the floor to Shining’s room; within seconds, much of the first floor was debris beneath his huge, expanding ass.

Dusk just kept moaning, shooting huge amounts of jizz up into the sky, which then splattered down over the wreckage and street before him. His hooves stretched down until they reached the sidewalk, every shift of his colossal body sending the ground shaking. Each spurt of Dusk’s orgasm sent hundreds of gallons of hot stallion cum splattering all over the street, covering it in a thick, sticky, musky white.

Shining flew through the air, his hooves waggling wildly and smacking against his huge, bloated belly. His mind was still awash in pleasure and shock, so much so that he barely even noticed when he hit the ground.

His massive belly spread out below him, a cushion that prevented any real damage. All the same, the impact set his whole body jiggling, his cum-filled gut sloshing from side to side as he moaned.

His vision swam before him. Shining groaned, blinking rapidly as he struggled to recover. Without Dusk plugging him up, a waterfall of cum poured out of his gaping asshole. Shining gritted his teeth and clenched his flanks. He could feel his hole slowly closing, slowly but surely returning to its normal radius. All the same, he still felt hugely loose. He had no doubts that he’d be walking funnily for the next few days. By now, his ass had only managed to close to around half of its maximum size, but enough of Dusk’s penetrating force lingered to keep it nice and wide as a river of hot, giant stallion jizz poured out onto the ground below.

The ground… As Shining’s belly slowly deflated, he let out another moan, his eyes fluttering open. The first thing he noticed was the odd color of the ground. It wasn’t the grass of the front lawn. Nor was it the red-and-white tiling of the street, or the cement of the sidewalk.

For some reason, the ground was...purple?

Shining blinked down at the surface he’d been resting on. Then he realized that he could still smell Dusk’s musk—stronger than ever, in fact.

He wasn’t on the ground—he was on Dusk. The “floor” below him was a vast, purple-furred sphere that only felt flat because of how large it was. Shining gaped as he slowly glanced up. His cum-filled belly squished slightly against the plump surface of what could only be Dusk’s equally cum-filled orbs. Soon enough, the rest of Dusk’s body came into view.

He was massive. He towered above the wreckage, his horn poking up above the nearest rooftop. Each one of his balls would have likely been close to dragging on the ground had he been walking; his shaft, which towered far above his head, was the biggest that Shining had ever seen, both absolutely and proportionately.

Dusk was leaning back, his forehooves crushing a pile of debris behind him. His chest heaved as he panted. Sweat poured down his forehead; every few seconds, the enormous shaft before him throbbed hugely, and he cried out before biting back down, whimpering. A steady river—and this time, it really was a river—poured down the side of his member, pooling between his balls before leaking down onto the grass below.

With a start, Shining realized that he’d just seen Dusk surge up again in size. His brother was nearly four stories tall, and he was still growing. Glancing back over his shoulder, he saw Dusk’s back hooves stretching toward the Canterlot road, his legs lengthening by the second.

Dusk appeared paralyzed with pleasure. He had both his eyes closed, and was panting madly. “Ooh, yes,” he moaned. “Growing feels so good. Gotta...get huge. Get so big. Get bigger and bigger and bigger.”

“Dusk?” Shining tried to pull himself to his hooves and just barely managed. His belly, though still round and taut from the amount of cum Dusk had pumped into him, was a bit more manageable now. At least it didn’t stretch past his knees, so he could still stand. “Dusk, you’ve got to try and stop growing! You’re getting too big!”

And he was. A hoofball-sized Dusk had been one thing, and a “tallest pony in Equestria” award would have been fine. Even a room-sized Dusk would have been okay, though he would have had a hell of a time fitting anywhere but the Palace from then on. But now...Dusk was getting way too big. Soon enough, he’d swallow up the entire street—and where might he stop after that?

One of Dusk’s eyes peeked open; for a second, he seemed to notice Shining. Then his monstrous cock throbbed again, and his eyes squeezed shut. His whole body shuddered. Sparks shot from his horn, and a visible purple aura pulsed around his body as his growth redoubled. “S-so hard,” Dusk panted. “Oh, this feels so good.”

“Dusk!” Shining hollered. “You’ve got to stop! You’ve got to—” He shut himself up. It was clear that Dusk wasn’t listening. He had to get his attention, or else find some other way to stop him.

Then his “little” brother’s dick throbbed again, and Shining had an idea.

Dusk’s moans echoed through the neighborhood. He was swaying lightly, his massive shadow falling over the houses below. More and more ponies were lining up on the street, gaping, as his gigantic form grew to swallow up the wreckage of the house.

And then he faltered. His moans paused—and then redoubled when he felt a pair of tiny hooves wrapping around his shaft.

Shining had his hooves stretched as wide as he could, and they still weren’t anywhere near wide enough to hold a meaningful fraction of his brother’s cock. Still, he couldn’t deny that the very act of pressing his body against his “little” brother’s stallionhood turned him on than anything they’d done before. Dusk’s giant slab of meat was pressed right up against his face, his chest, and his crotch, his growing brother’s shaft rubbing against every inch of his body.

Dusk groaned, his eyes fluttering just the tiniest bit open as Shining pleasured him with his entire body. Their incredible size difference was clearly turning him on, driving him further toward the edge. That was just what Shining wanted.

“Sh-shining,” Dusk groaned. His voice boomed out across the neighborhood. “Shining, I’m so big.”

“Yes,” Shining mumbled. He doubted Dusk could even hear him like this, given how much noise Dusk's  giant body was making, and how tiny he was by comparison. “Yes, you are.” He redoubled his efforts, humping Dusk’s shaft as hard as he could.

“So,” Dusk mumbled, “so, so big.” Everypony in the neighborhood could see him now: his huge, swelling body, splattered with enough cum to fill a small lake, muscles swelling and rippling beneath his coat. “Oh, Shining, I’m just so huge.”

A glob of pre, as wide across as a wagon, burst from his tip. It landed somewhere on the street, right among the gathering crowd. Several ponies shrieked and dodged away. But Dusk didn’t seem to care. He went right on panting, went right on growing, still stroking the tip of his shaft as Shining humped the bottom.

“Yes, you are,” Shining said, almost in a whisper. He closed his eyes, imagining. The rush that Dusk must be feeling—the allure, the pleasure of ever-increasing size—must be...intoxicating. The euphoria that must be filling his every muscle, the duel between reason and lust as his libido grew to unbridled heights—even imagining it was incredible.

Dusk’s eyes may have been closed, but Shining could tell that his once-shy brother was revelling in the attention of the gathering crowd. The feeling of strength, of absolute dominance his enormous body created, was almost stifling. Shining took a deep breath, filling his lungs with Dusk’s intoxicating scent as he humped his brother’s house-sized length again and again.

To be so big—Shining wanted it so badly. To feel yourself expanding, swelling, outgrowing everything and everyone you had known before. To throw out your limbs farther and farther every morning, to see the ceiling getting ever-closer—and then, once you’d outgrown the ceiling, the very sky itself. Shining wheezed, gasping as arousal pulsed through his veins, Dusk’s all-encompassing lust for size pumping through his veins.

“I wonder—” Dusk gasped, surging up in size and losing control for a moment. His titanic cock throbbed, soaring above the houses below. “—I wonder—mmff—how big I’ll get, Shining.”

Oh, Shining had an idea of where this was going.

“Bigger—nggh—than you,” Dusk said, panting. “Bigger than the house. Maybe bigger than—ooh, yes—Canterlot. And maybe—I’ll be strong enough—to get bigger than all of Equestria.” He shuddered, his whole body going erect with dreams of size. And his stallionhood trembled.

It was clear how much his fantasizing was turning him on. The river of pre down his length doubled in width, becoming a warm, thick flood of lust running down his meaty shaft. Shining joined him in his fantasies, squeezing his eyes shut as he rubbed his whole body along Dusk’s length, dreaming of being big.

Big. Huge. Enormous. Gargantuan. Towering over other ponies—over rooftops—over entire cities, always growing, never stopping, always lusting for more and more and more—

Shining bit down on his lip, squeezing his eyes even more tightly shut as a wave of arousal shuddered through him. With his eyes closed, though, he didn’t notice when the shimmering purple magic around Dusk’s body flickered—then spread to cover him, too.

Shining had only been slightly wrong before. Though his hooves and body were mostly far too small to please Dusk effectively, the simple fact that his once-big brother had been reduced to using his whole body to jerk him off had turned Dusk on like nothing else. To feel Shining’s whole body against his base—to know that other ponies were almost like mice, or like insects to him now—drove his arousal to new heights. Dusk had never been a mocking or elitist stallion, but the feelings dominating his body right now threatened to overrun everything else.

Yet Shining wasn’t quite so small anymore. Dusk’s magic was flaring, burning around him, the sheer energy of the giant colt’s magic actually evaporating off of his fur—and leaping into the nearest available host. Shining shuddered, his whole body going erect as Dusk’s magic flared inside of his chest. At first he felt dizzy; then, he felt a tingling dancing up and down his spine. A feeling of aroused bliss was spreading throughout him, a physical euphoria greater than the most powerful aphrodisiac.

And he was growing. Not as much as Dusk—nowhere close, really—but with each breath Shining took, his body swelled a little bit upward, a little bit outward. At first it was just an inch, then two, then four—every hump, every grind against Dusk’s magnificent shaft bringing new size to Shining’s growing body.

Dusk’s shaft was still far too wide for even him to fit both hooves around it, but Shining was growing fast enough that, suddenly, just hugging it didn’t seem so impossible. Dusk’s eyes fluttered open, his breath catching, as he felt the “insect” rubbing against his meat suddenly become a chipmunk—and then a squirrel. Shining was growing, and the bigger he got, the more he could pleasure his also-growing brother.

By now, Dusk was nearly forty feet tall, just sitting down. So much precum had streamed down his dick that he’d drenched Shining in it entirely, covering him and the entire surrounding area with a thin, milky-white finish. Shining gritted his teeth, only partially conscious of his swelling body—he was more than seven feet tall now, had he been keeping track—and just grinded his body even harder against Dusk’s.

Something was rumbling beneath Shining’s hooves: Dusk’s balls, a pair of massive, cum-laden nuts huge enough to reach nearly halfway up his stomach. Dusk was wheezing, gasping for air as his massive body reached a level of peak arousal. Shining just clenched his teeth, humping even harder as he felt himself approaching his own peak. He wanted to cum with Dusk—needed to cum with him. He no longer cared about stopping him; he just wanted to see his brother grow bigger and bigger until there was nothing else left to outgrow—

Dusk’s hips were jerking, slamming onto the ground every time he pumped his shaft beneath his hoof. Each slap of his flank against the ground caused a miniature earthquake; his massive, several-ton body was absolutely enormous. Shining didn’t even care. So what if it was a little hard to hold on? He needed this—needed to feel Dusk’s stallionhood against every inch of his body, rubbing himself against it, covering himself in his once-little brother’s musk as he ascended to unfathomable heights.

By the time Shining had reached nearly one and a half times his original size, Dusk was approaching fifty feet. With so much size, so much growth, so much lust roaring through both stallions’ systems, there was only one place for all that arousal to go.

Out.

The rumbling reached its peak—then paused. A mighty, terrible shudder echoed through the earth.

Then Dusk’s orgasm exploded.

A tidal wave of spooge burst from his tip, his shaft flexing hugely as it erupted with cum. Dusk’s massive, spongy head puffed up, bulging as a flood of cum burst from its depths. Gobs of spunk, each one bigger than a full-grown stallion, rolled down his length and nuts. Dusk’s moans reached a roaring crescendo, his whole body twisting and jerking as he rapidly pumped his massive shaft.

Shining came with him, crying out in overwhelming pleasure as he felt Dusk’s girth lurch and shudder against his chest. There was no doubting how much Dusk had needed this—how much he’d needed to cum, struggling to keep his titanic load down against an overwhelming urge to find release. And now, in this moment, Shining found release with him.

Cum kept erupting from Dusk’s flare like from a volcano. Huge globs of thick, creamy white cream splattered the nearby rooftops, painting the town white. Shining couldn’t imagine how incredibly, impossibly full his brother had been, how painfully pent-up his growing size had made him feel—and how good it must feel now to drench the neighborhood in his jizz.

He moaned, rubbing against Dusk’s shuddering shaft as thick gooey spurts of his own cum painted Dusk’s girth white. Dusk’s prodigious amounts of spooge were actually pooling into ponds and lakes around the lawn and on his own massive ballsack; a swelling pool of jizz, hot, musky, and creamy was lapping at Shining’s hooves, staining his fetlocks a thick creamy white. Each lurch of Dusk’s cock brought another ton of jizz arching through the air before it crashed down on the pedestrians below, bathing the street in his spunk.

Jets of Dusk’s giant-sized orgasm spattered noisily against the road and buildings alike. He gasped, his whole body shuddering with pleasure as he fired shot after thick, gooey shot into the air. Shining was writhing against his brother’s length, overcome with pleasure as he was absolutely drenched in his brother’s cream. It just kept coming: a torrent of cum, a cascade of spunk so thick and virile that it seemed endless, even as Dusk’s orgasm tried to drain every last ounce of cum from his nuts.

And then, finally, it was over. Dusk gave a final moan as his cock gave one last throb—then flopped back onto the yard below. He groaned, his hooves digging out deep gouges into the ground. Shining gasped as he found his anchor—Dusk’s titanic shaft—bending forward over his brother’s torso. Then he yelped, losing his balance and tumbling hooves-over-head until he came to a rest on top of Dusk’s cum-splattered belly.

Shining groaned. His head was spinning, and he felt sore all over. Rubbing his horn, he grimaced, then slowly raised his head—to see Dusk grinning down at him.

Dusk may have been lying down, but his head was still so much bigger than Shining that he had to look down to meet his eyes. Still, Shining could easily see the bright light dancing behind his brother’s eyes—not the flaring, lust-driven gaze he’d had before, but the intelligent spark he’d always known his brother to have.

It looked like Dusk was back in control.

He was blushing hugely, though his smile stretched from ear to ear. “Wow,” Dusk said. “That was...uh, something.”

“You can say that again,” Shining said. It was still sinking in just how big Dusk was compared to him, but at least he didn’t seem to be growing anymore. Though for some reason, Dusk seemed a bit...less huge than before. Huh. He blinked rapidly, feeling lucidity returning to his thoughts.

Dusk grinned sheepishly. “I, uh, saw what you were doing down there. That was really hot.”

“Oh.” Now Shining was blushing, too. “Glad you liked it. Heat of the moment, I guess.”

“Mmff.” Dusk peered down at him, blinking with a pair of pony-sized eyes. “Huh. You look a little...bigger than you did before.”

“Maybe you just shrunk?” Shining offered. Then again, he noted, glancing around at the other houses, there was little chance of that happening.

Dusk chuckled. “Don’t think so. But you do look different.”

Shining glanced down at himself. Then he glanced at the crowd of ponies down in the street. Funnily enough, they did look a bit smaller—and it wasn’t just because he was perched on Dusk’s chest. “Wait. You think—”

“That some of my growth spread to you?” Dusk beamed down at him. “Maybe.”

Shining opened his mouth to reply, then grunted as a sudden weight swept him to his knees. Squinting to his side, he saw Dusk’s hoof, which wasn’t quite bigger than he was anymore, pressing him down. Then he realized: Dusk was hugging him. Or at least as much as any fifty-foot tall giant could hug a much smaller pony.

Dusk laughed softly, hugging Shining to his chest. His oversized hoof wrapped around his brother’s middle, pressing Shining against his cum-stained fur. “Growing feels really good,” he confessed. “But...it didn’t feel half as good without you helping. So thank you. For helping me feel good.”

Shining struggled against the weight of Dusk’s hoof, then decided to give up. Instead, he squirmed himself into a more comfortable position on his brother’s chest before glancing up again. When he did, he noticed that Dusk’s big cheeks were bright rosy red. That was when he realized that his own cheeks were burning as well.

“Um,” Shining said, grinning. “I liked it, really. Making you feel good. And seeing you get so big was just—man, words can’t even describe it.” He snuggled against Dusk’s chest, pulling his brother’s hoof closer around his middle. Dusk looked surprised for a second, then smiled drowsily.

“Mm.” Dusk’s eyes fluttered a bit. He began to massage Shining’s back gently, his touch surprisingly light for how heavy his hoof was. “Shining…”

“Mmhm?”

“Would you want to be big too?”

Shining yawned. The afterglow of his cumulative orgasms was spreading throughout his body, making his every muscle feel lethargic. “Mm. You bet I would.”

“Mm.” Dusk began to rock his big body back and forth, still rubbing Shining’s body. “Maybe we can...find a way to make you as big as me, then. A growth spell or something.”

“Really?”

“Mmhm.” Dusk’s smile softened. “Dusk ‘n Shining. Biggest stallions in Equestria.”

“Heh.” Shining snuggled further into Dusk’s chest. “I think I’d like that.”