Horizon's hooves were throbbing as he finally plopped down onto his bed.

His legs were sore and covered in dirt after a long day spent shoveling dirt and harvesting crops. He'd used his magic, but that hardly mattered—when you were out in a farm, the mud and grime got everywhere. His tail, matted with dust and plant matter, flickered weakly in the air as he lay staring up at the ceiling.

I should really take a shower, he thought, knowing very well that he wasn't about to do any such thing. His warm bed felt so comfy, and the bathroom was so far away. He shifted his back, the sheets crinkling under his weight.

A warm, earthy smell drifted across his nostrils, and he smiled. He could see them out of the corner of his eye, green stems rising high into the air inside of his room. His plants. Not the dirty, mass-produced potatoes out in the northern fields. His plants.

He turned his head so that his ear was barely touching the pillow, letting his eyes rove over the familiar sight of his bedroom wall. Long vines of ivy grew along the wallpaper, their leaves folding outward to cover most of the original floral pattern that had sat on the plaster behind them.

He'd never liked that wallpaper anyway. The flowers were too small for his taste.

Beside the vines grew another cloud of brush: strawberries, their stems bowing low to the ground with the weight of their fruit. He pondered snacking on one, but discarded the thought. Even just one would be too big to finish, especially this late. That was what happened, after all, when you grew berries that were half as big as your head.

Two sycamore "saplings" grew from either side of the vines. They'd sprouted barely two weeks earlier, but were already above his shoulder. Another few days, and he'd have to remove them from the clay pots he'd used to raise them, and transplant them into the garden outside. A small smirk crossed his face. Then again, maybe that wouldn't be so bad—they'd give his watermelon patch some company. Those stallion-sized melons could get lonely, after all, especially when almost nopony ate them out of sheer awe.

Horizon had a talent. He'd had it, really, since he'd first stepped into his parents' garden when he was only six. Even though he hadn't had his cutie mark yet, his mother'd taken notice that everything he cared for seemed to grow a little better; every plant he'd fed and watered grew a little taller: a little more vibrant.

And then he'd gotten his cutie mark, and things had really gotten out of hand.

His signature spell—his friend Blaze had named it—the "Grow Me Up" spell, had landed him a pretty high-paying job with a local team of farmers almost instantly. He'd tripled the size of their potatoes, quadrupled the volume of each pumpkin, and made their fields of corn produce so much food that they hadn't nearly been able to sell it all. Almost overnight, Cherry Dun Acres had become a talking point among the suburbs of Fillydelphia.

Sometimes, the other farmhands cornered him and asked if he really could double the size of any fruit or vegetable in under a minute. They'd been much more disappointed when he'd disabused them of the notion; he could increase the size, but only with repeated bursts of the spell over a long period of time. It wasn't some miraculous instantaneous growth serum, though his boss definitely wished it could be.

His eyes fluttered closed, and he yawned. An image flashed across his vision—Apple Blossom, the earth pony mare who'd started work at the farm just three weeks ago.

He licked his lips. She'd caught his eye—and those of nearly everypony else—immediately. In his mind's eye, he pictured the perfect curve of her body, the roundness of her flank; he saw the glimmer in her eye, her tongue curling around his ear as she—

Horizon felt a warm feeling between his legs, and looked down to see the tip of his sheath swelling, just slightly. His cheeks tinged red, even though he knew, rationally, that there was nothing to be embarrassed about. Hesitantly, he reached down with his right forehoof and stroked gently across his crotch.

The contact felt good, and he did it again, a little harder. He was holding Blossom's picture firmly in his mind, now, that glorious flank the only thing filling his vision. He felt a soft rush of air against his groin—his package had gotten hard enough to spring free of its sheath.

Tenderly, he took hold of his cock, one hoof running down its veined side as it stood at attention. The other fondled his balls, his legs spread wide enough to allow them enough room to rest comfortably on the warm sheets beneath him. Up and down he stroked, his hoof gliding over the tip of his dick as it reached its full length—a respectable seven inches. His eyes fluttered shut, and he gave it a quick squeeze between his hooves. The veins throbbed, and a wave of endorphins exploded in the back of his head. The first—and smallest—of many.

He later couldn't say whether it'd been the smell of the soil in his room, or the image of Apple Blossom, picking cherries from a bush, that put the idea in his head. But somehow, for the first time, Horizon wondered whether his growth spell would work on himself.

Maybe it was the summer heat throbbing outside his window; maybe it was the fatigue, built up over hours of hard labor. Whatever the reason, though, he decided that he wanted to see whether he could make his cock any bigger than it already was.

He nearly snickered at the thought—how many stallions had gotten suckered with the back-alley promises of "pills to make your dick bigger?" Then again...he didn't feel small or anything, but he'd seen other stallions out in public—it was inevitable, given the nudity of most ponies, that you'd see at least a few unintentional boners a month—and it'd be nice to turn his seven inches into ten. Or maybe a foot. He shivered with tentative glee.

Biting his lip, he fidgeted backward until his back was leaning against the headboard of his bed, his dick pointing straight toward the ceiling, and summoned up his magic. By this point, the "Grow Me Up" spell was nearly automatic for him—he'd used it so many times that it was almost second nature for him. It was his special talent, after all—the giant sunflower on his flank said as much.

He didn't expect much—maybe a quarter of an inch, at most. He knew how his magic worked. If he wanted any real change—assuming the spell even worked—he'd need to use it consistently, and over a period of at least a few weeks. He grinned, feeling a bit giddy. But what a difference! Surely the wait'd be worth it.

His horn glowing green, a flash of white light erupted from his tip, and the spell was activated.

He watched it expectantly, wondering what, exactly, would happen. His lip curled slightly in disappointment, though, when the his penis did absolutely nothing. No change; no growth. He squinted; yep, still looked like seven inches to him. It looked like his spell only worked on plants after all.

Eyes closing, he sighed and summoned up the image of Apple Blossom again. Ah, well. He'd have to make do with his regular size—not that there was a problem with that. In his mind, his hooves wandered down the sides of her hips, whispering across the roundness of her flanks, and stretching her cheeks wide as he thrust forward toward her—

Even with his eyes closed, he knew something was off. He'd been stroking his cock with one hoof, his dextrous limb curled around the side, but it felt as though it'd been pushed back a bit. As though his hoof was suddenly in contact with more skin than there had been before. At first, he dismissed it, but as the sensation grew, along with a blossoming warmth between his legs, he finally opened his eyes to see for himself. He gaped.

As he watched, the tip of his cock inched up into the air above his balls, getting just a little bit closer to the top of his chest. A grin spread across his face, at first in disbelief, and then in sheer giddiness. It worked!

He stroked it again, and he watched in amazement as his cock grew just a little bit more. He estimated it at nine inches now. Incredible. And it felt good—nothing earthshattering, but each touch felt just a little more pleasurable; a little more electricity running up his spine. As his right hoof ran up and down the base, his left hoof teased the tip, going in little circles around the head. He moaned quietly, shivering.

I'm gonna need some lube at this rate, he thought. One hoof broke off from its play and reached toward his bedside night table. He kept a small jar of lubricating cream in there that he usually kept hidden in a drawer. As his hoof extended toward the drawer, though, his eyes widened, and it stopped in place. His dick was visibly swelling, now twelve inches in length—no, thirteen!

His balls felt heavier, and as his eyes flickered down toward them, he realized that his formerly ping-pong sized testicles were now nearly twice the size they'd been before. He idly gave them a soft stroke and nearly shivered with pleasure, the sensation flashing through his mind like no other.

I don't think I'll need lube... he thought, watching his rising dick with something approaching hunger and self-lust. It was better than he could've ever expected—Take that, Big Dun, he thought with a smirk, picturing the elder farmhand's now inch-smaller cock in his mind's eye. He swallowed, watching his dick grow until it poked up just past thirteen inches. The growth paused, and Horizon felt the magic fading from his horn. Saliva built up in his mouth, and he licked his lips. There was something that he'd always wanted to try; something that bigger stallions had always been able to do, but which he'd never been quite able to manage...

Hesitantly, he bent down and took the head of his cock into his mouth.

He felt its warmth as it sat on his tongue, two inches of pony cock resting in the cavity of his mouth. His saliva was even better than he'd imagined, lubricating the tip and just barely sliding it back and forth with each swish of his tongue. A cautious swirl of his tongue across the head made him shiver with pleasure, the electric feeling jolting up his spine and right into the pleasure centers of his brain. Slowly, taking care not to go too quickly—he didn't want to go too hard too fast, and so ruin the experience—he pushed his head down until he held the whole head in his mouth. The mushroom-shaped tip was heavy, and it filled over half of his mouth with its sheer girth. It had to be at least two to three inches wide at this point.

Up and down his mouth went, sliding across the engorged veins that stood up from the sides of his cock. He thrust his head further and further down, teasing the nerves as his hooves played with his balls. By now, they were the size of large nectarines, and ached with a need for release. Down and down he went, his tongue swirling around the sides of his cock with each teasing flicker. He took in more and more: four inches; five inches; six.

He removed his mouth completely from his dick and took a deep breath. It sat there invitingly, standing tall in the air with a strand of warm drool dripping down its side. He took two more breaths, filling his lungs—and then dove right in.

He passed six easily, hitting eight—eight! The head bumped against the back of his throat, but still on he went, determined to make it all the way. Ten inches—the warm, moist tube of his esophagus curled around the length of his swallowed cock, each contraction of the muscle squeezing and stimulating. Twelve—his eyes were watering; he was so close. His mouth was opened even wider now, the ring at the base of his cock fitting just between his spread jaws—

—Thirteen!

His eyes opened wide as his lips brushed against the tops of his balls, the enlarged testicles groaning with pent-up frustration and a need for release. With a jolt through his whole body, beginning in his groin and going all the way up to his mouth, he released that that tension was about to burst.

Instinctively, his mouth opened even wider, his hips bucking and thrusting forward as the orgasm came. It felt like a rush of fiery pleasure, the sensation spreading through his entire body as he came—

—But no cum came out.

His eyes going wide, he felt the magic building up at the base of his horn again, except this time, he wasn't controlling it. The green-tinged aura built up at its tip, flickering in his peripheral vision, and, with some alarm, he felt his cock swelling inside of his mouth. Down it pushed, slipping out of his throat with a wet popping sound until he had only six inches left in his mouth. The width increased, too, pushing against his gums and filling the entirety of his mouth. He groaned weakly, the tightness of his own mouth arousing him even more, but terrifying him as well.

Oh, shit—

His ears flickered at a crackling noise, his jaw popping as his cock forced it open even wider. Still it grew—though his eyes were locked into a position somewhere between forward and down, he could estimate the length already at fifteen or sixteen inches—and still growing. Seventeen. Nineteen.

He moaned, terror and pleasure warring amongst each other in his mind. With a final crack, his jaw settled into place, the cock sliding no further out of his mouth. He was filled with seven, saliva-covered, jaw-splitting inches of stallion cock, and still, he was growing. Crap! I can't even pull it out anymore! When's it going to—oh...oh...

His balls swelled as his dick reached twenty inches, stretching his neck back by a few degrees. They throbbed and pulsed on the sheets, forcing his legs apart with sheer girth. They were easily the size of apples now, if not large oranges. Bigger and bigger they grew, his unleashed seed churning and swirling within their blossoming depths. His back arced and his hooves spread wide—as he reached two feet, all fear was gone, replaced only by a towering monolith of pleasure and pain.

His tongue, massively undersized for the gargantuan job it faced, lapped greedily at the sides of his dick that it was able to reach. His veins, throbbing with blood and magic, pressed against his cheeks, swelling outward. The pressure was incredible, the tightness insane. Almost unconsciously, and almost counterproductively, he thrusted with his hips, forcing his dick even deeper into his mouth. It hit against the back of his throat; he thrust again, and the entire organ, all twenty-four inches of it, shivered in pleasure. Something warm; something moist and sticky seeped out of the tip, and he eagerly swallowed all of the precum that he could get.

His hooves ran up and down the sides, squeezing its incredible girth and fondling his growing balls. He couldn't even reach his hooves all the way around its circumference anymore, and his balls churned, complaining loudly for the release of his seed. He swallowed, the contractions of his tongue and throat squeezing his head and stimulating him further. His lips, suckling at the one-third mark down his cock, popped wetly off of the sides before sucking again at the immense piece of flesh.

He passed two feet without breaking a sweat, and that was when he felt the tension building up again. A huge pressure, piling up at the bottom of his nutsack as each testicle reached the size of a soccer ball. By now, they rested halfway on the bed and halfway on his exposed stomach, radiating warmth, musk, and need.

The rate of suckling increased, his mouth moving up and down all two inches that it could as his jaw spread even further apart. He felt the tension grow even higher, the sensation spreading up his cock, raging through his veins, and tingling in his mouth as he gave one, final thrust.

The dam broke.

It's all going down my throat!

Like a flash flood, cum burst from the head and surged into his throat, bypassing his mouth entirely. What felt like quarts, or even gallons of warmy, sticky seed flooded into his mouth, clinging to his esophagus and dripping down to his stomach. He moaned as the electric sensation surged along his spine and he thrust forward again, forcing his jaw even wider as he pumped torrents of cum into himself.

His balls churned and cheered, the enormous pressure finally lessening with each wave of cum that flooded from their engorged depths. Whenever he'd cum before, it'd been a few streams of discharge; a couple of long, sticky strands that exploded from the tip. This, though, was nothing like that—it was a flood of warm seed that was bigger, warmer, and infinitely more pleasurable than before. He felt it building up in his stomach, his belly swelling outward with each pump of jizz. His hooves roamed across his body as he thrust reflexively, stroking across the veins of his cock, cupping his swollen balls, and rubbing his growing, cum-filled stomach as it grew more and more, the pressure in his balls lessening with each pumped quart of semen.

Some white-colored spunk dripped from his mouth, seeping past the huge width of his cock and dribbling down onto his chest. Finally, though, he felt the deluge slow, and then, after what felt like days, come to a full stop. His cock already shrinking and his boner disappearing, he felt the moist dick pop out of his mouth before coming to rest on his massive, cum-filled stomach.

He lay there, stupefied, and staring up at the ceiling with wide, dilated eyes. Small jolts of pleasure seemed to run through his body every few seconds, fading with intensity as his dick shrunk down to a more reasonable size. More semen dribbled out of his mouth and onto his stomach and chest.

Horizon let out a long, shuddering sigh of pleasure. It seemed appropriate.

A dreamy sort of smile crossed his face. That was...incredible. Amazing. It was better than anything I'd ever had. He lay there for a few moments more, basking in the afterglow and imagining Apple Blossom's reaction to his massive, beautiful stallionhood. He pictured its warm, full musk drifting to her nose, the full organ standing marvelously before her eyes—

He froze, and his eyes slowly drifted down to where his still-massive cock rested on his stomach. He swallowed, feeling the sticky remains of cum coating his throat.

"Oh, crap," he said aloud, eyes wide. Twelve inches of flaccid stallion cock lay quietly before him. "That is going to be hell to hide."

It was only after he'd turned off the lights, the blankets feeling warm and distant above his engorged belly and cock, that he realized that he still needed to clean up the mess he'd left.

Shit.