Rainbow was really starting to miss her nap.

When she was younger, the single Royal Guard assigned to keep the peace in Ponyville had made it his solemn duty to track her across town, interrupting her daily naps with complete disregard for the vital role they played in her training regimen. It didn’t matter how many times she explained that she was an up-and-coming Wonderbolt or that she needed her twenty minutes of power-sleep to recharge her batteries after a session of hardcore flying. Did he listen? No, he’d just grumble some nonsense about truancy and laziness, as if she weren’t the most radical young mare in town.

But the joke was on him, cause now he was retired and she was a Wonderbolt and a national heroine, just like she always said she’d be. And the new Ponyville Guard worked for Twilight, so now Rainbow could nap wherever she wanted and nopony could do anything but give her a disapproving look.

On the other hoof, being friends with Twilight also meant that Rainbow sometimes had to skip her naps to help test new spells.

“Are you almost done?” Rainbow asked, blowing her mane out of her eyes. She was standing in the center of Twilight’s ‘test chamber,’ a room which—if Rainbow were being honest—looked pretty much the same as every other room in the castle. It was crystal, and full of books, and there was a big desk off to one side covered in neatly organized notes. There were also the arcane runes engraved on the floor and behind all the paintings on the walls, but Rainbow normally didn’t look at them, so she didn’t think those counted.

Twilight hummed as she chewed on her quill. “Just about.” She let out a little gasp and scribbled something on the book floating in front of her, then went back to her thoughtful chewing.

“That’s what you said last time!” Rainbow let out an exaggerated sigh, slumping her shoulders. “This is taking forever.”

“Rainbow, the last time you asked me was thirty seconds ago, and you’ve only been here for five minutes.”

“Every minute counts, Twi!” Rainbow countered. “I have a very tight schedule, you know.”

“I’ve seen your schedule.” Twilight lowered her book enough to frown at Rainbow with her eyes. “It’s only two blocks, one labeled ‘sleep’ and one labeled ‘fly,’ and they aren’t even clearly delineated.”

“Yeah, well, I keep most of it in my head. You wouldn’t get it.” Rainbow pursed her lips, looking away indignantly.

Several seconds passed in silence.

“So like, are you almost done?”

“Yes, actually.” Twilight smiled as she snapped the book shut, floating it gently over to her desk. “I appreciate your… patience, but I need to focus now. If you could just stand in the center of the room and clear your mind, then we can start the first trial.”

“Awesome.” Rainbow pushed off the wall and stepped into the middle of the room, turning to face the door like she always did. “So what’s this spell for again?”

“I’ll tell you after,” Twilight said. “It’ll contaminate the results if you know ahead of time, but just try to think about nothing for now.” She took a deep breath, closed her eyes, and scrunched up her muzzle as her horn began to glow.

Rainbow grunted, looking around in search of something to distract her while she waited. Books, more books—and none of it the good books that she liked. It was all Twilight books, the kind with three long titles, each one smaller and harder to read than the one before it, where the first thirty pages was the table of contents.

She ended up looking out the window. They had clear weather today, as Cloudsdale had recalled some of their rainwater reserves to help with a shortage in some other part of Equestria. It had been a long time since Rainbow did any real weather work; she was a Wonderbolt now, and really just didn’t have the time for it. She’d left the job of Ponyville weather manager to Thunderlane, who was pretty good at it, even if not as good as she was. She sighed as she thought of all the hours she’d spent with him in the Ponyville sky, kicking clouds and making rain. Was he still dating Flitter? Rainbow had always kinda wondered what he was like in bed. How could she not after seeing the way he bucked a cloud?

She’d mostly lost interest in him since joining the Wonderbolts, though. Her fillyhood crush, Soarin, was more available than ever, and she’d snuck a few peeks at his package during practice. Those tight flight suits really didn’t leave anything to the imagination.

Wait.

What if Soarin had been ogling her?

It’d make sense. She was pretty awesome, and if she was in his place, she’d definitely be stealing looks under her tail. The flight suit was so tight it felt like flying naked, and it might as well look like it, too.

Rainbow was so lost in her thoughts that she didn’t register the kaleidoscopic display of magic in the room until it quite literally hit her in the face.

She yelped, every muscle going rigid as a sharp electric tingle raced through her body. Her eyes screwed up and her mane and tail shot out, and suddenly she was on the floor, blinking up in confusion at the spinning ceiling as Twilight’s voice echoed in her ears.

“Oh my goodness! Rainbow, are you okay?”

“Eugh.” Rainbow shut her eyes and rubbed at her forehead with a hoof. “What the hay, Twi?”

“I’m sorry! That wasn’t supposed to happen!” Twilight sounded worried. Then again, she always sounded at least a little worried. “Just hold still and let me look you over, make sure there’s no lasting damage, and—o-oh.”

Rainbow’s ears perked up at the sudden alarm in Twilight’s voice. “What? What’s wrong?”

“Well, um.” Twilight let out a forced laugh. “N-nothing! Do you, uh, feel any different?”

Rainbow opened her eyes to see Twilight looking down at her with an anxious smile. Thankfully, the room had stopped spinning, so she fluttered her wings and rose into the air with a little twirl—a lopsided little twirl.

She frowned. “My balance is off.”

Rainbow considered her body to be a finely tuned engine of awesome. And as the sole pilot, engineer, and maintenance mare of said engine, it didn’t take long for her to figure out where she’d picked up extra weight.

She looked down, between her hind legs, and her eyebrows disappeared into her mane.

“Twilight,” she started cautiously. “Why’ve I got a dick?”

“Everything is fine!” Twilight assured her, already pacing around the room in that way she did when everything was wrong. “This is what testing is for!”

Rainbow barely heard her. She was too fixated on the foreign object nestled cozily between her legs as if it belonged there. It wasn’t erect, thankfully, but the short hairs over her sheath were a darker blue than the rest of her coat, almost like the blue of her mane. She reached a hoof down to poke at her balls, feeling their weight, and let out a surprised coo at the pleasurable tingle as she caressed the velvety smooth skin wrapped around them.

She drew her hoof back quickly. That was weird.

Wait, what about—

She bit her lip as she reached further back, under her tail, and let out a relieved sigh as she felt the soft folds of her marehood. At least that was still in place.

“Alright, so, uh, how do we get rid of this?” Rainbow asked. She turned to face Twilight. “You’ve got a spell for that, right?”

Twilight didn’t answer. She just stared at Rainbow’s new package open-mouthed, freezing with one hoof off the ground, and Rainbow felt a strange shiver pass over her, gone as quick as it came.

“Uh, Twi?” Rainbow hovered closer and waved a hoof in her face. “You there?”

“Huh, what?” Twilight blinked, finally meeting Rainbow’s eyes. “Sorry. I was just, um—well, we should, uh—” She perked up with a tentative grin. “We should run some tests!”

Rainbow groaned. “Do we have to? I don’t really have time to stay cooped up in here all day while you play with my new dick.”

“It’s not playing!” Twilight insisted, trotting back to her desk. “It’s science!”

Rainbow rolled her eyes and settled back onto the ground. She tapped a hoof impatiently, watching Twilight mutter to herself as she sorted through her notes. She’d really filled out since becoming an alicorn, hadn’t she? Rainbow wasn’t super into mares, but even when Twilight had first come to Ponyville anypony could tell that she had an endearing cuteness about her. Sure, she’d been a little thick around the barrel, lacked a certain firmness in her hindquarters, but some ponies liked that.

Things changed once she became an alicorn, though. She’d grown taller, slimmer, not anything like the older alicorns yet, but it was an obvious difference. She’d both put on extra weight and gotten tighter all around, and Rainbow found herself mesmerized by the sideways sway of her flanks as she stepped from one end of the desk to the other. Sweet Celestia, when did her ass get so firm? Was she clenching her buttocks right now or was that just how she looked, even relaxed? Rainbow licked her lips, tilting her head to one side to try and get a peek under her tail. She’d caught glimpses before, but she’d never paid much attention until now.

“Hey, Twi,” she said. “Lift your tail.”

Rainbow blinked, cheeks warming in a deep blush. Where the hay did that come from? She opened her mouth, already considering how to phrase her apology, when—to her shock—Twilight’s tail hiked almost straight up.

Rainbow froze, unable to look away. Twilight’s marehood was fully exposed, a pair of puffy purple pussy lips with a neat little slit tucked away between them. They swelled out towards the bottom, parting ever so slightly to reveal a sliver of ripe pink inside, pouting up as if to beckon for some lucky stallion to enter.

And she was wet.

“Um.”

Rainbow stiffened, looking away from Twilight’s honeypot and meeting her wide eyes. There was that weird shiver again, tingling down her spine.

“I’m not, um—” Twilight blushed, looking away. “Do you like it?”

“Y-yeah.” Rainbow swallowed. What in Equestria was going on? Where were these thoughts coming from, and why had she said that, and why did Twilight actually listen? She was still just standing there, tail up, baring it all, and Rainbow found her gaze drawn inexorably back down.

She licked her lips, stepping closer and raising a hoof to Twilight’s flank. The alicorn tensed, but didn’t move away, and Rainbow felt a strange twinge between her legs at the way her friend’s muscles moved underhoof. This was nothing like the soft librarian that had first come to Ponyville. Twilight’s ass was firm and supple, giving when pressed on and then springing back quickly when released. Her buttocks seemed almost to squeeze together from both sides, pushing her pussy out as if it could barely fit in the space between.

A bead of arousal formed at the bottom of her marehood, pooling within her upturned lips. How did it taste? Rainbow leaned forwards, sliding her tongue across it from the bottom to top.

Twilight gasped. A soft, feminine sound that tickled at Rainbow’s ears, halfway between shame and lust. Her pussy winked, clenching around Rainbow’s tongue with surprising strength. Her excitement flooded past Rainbow’s lips, the tangy flavor exploding in her mouth before dripping down to splatter against the crystal, and a powerful shudder rocked Rainbow’s body as her cock slid free of its sheath, tingling with an excitement she’d never felt before.

“Wait.” Twilight pulled away hesitantly, leaving Rainbow’s muzzle slick with her flavor. “Something’s happening here.”

Rainbow didn’t respond. She stepped closer, leaning in to steal another taste.

“Rainbow!” Twilight rounded on her, planting her rear firmly on the floor. Her cheeks were flushed and her chest was heaving, but the concern was clear in her eyes. “I think it’s the spell. It’s having some adverse effects on us, making it hard to focus.”

Rainbow’s nostrils flared. Her cock slapped against her belly, leaving a wet dab of pre. Her words seemed to buzz as they left her muzzle, leaving her lips briefly numb. “Turn around.”

Twilight obeyed instantly. She stood up and turned around, tail flagging high, but her voice sounded confused. “Rainbow, focus. Don’t you remember why we’re here?”

“I know why I’m here,” Rainbow said, breathing in a deep draught of Twilight’s mare scent. “Bend over.”

Twilight moaned as she lowered her head to the cool crystal, presenting her pussy. The swollen lips winked, her pink clit glistening as a fresh wave of arousal dripped down her thighs.

Rainbow’s body moved on instinct. She reared up, sliding her chest over Twilight’s rear and grabbing it tight between her hooves. The tip of her cock landed against Twilight’s pussy with a wet slap.

“Ooh,” Twilight cooed, moving her hips in a slow circle. The wet folds of her lower lips teased around Rainbow’s tip. She went rigid a couple seconds later, looking around with unfocused eyes. “This feels… weird. Something’s—something’s wrong.”

Rainbow wasn’t listening. She was focused intently on the soft, winking honeypot slathering her new cock with femme excitement. She could feel Twilight’s pulse through her pussy, beckoning her inside.

She couldn’t wait any longer. She pulled on Twilight’s hips and threw her hips forwards. There was a brief, immeasurable moment of resistance as Twilight’s tight lower lips held firm, and then—with a sudden, powerful wink—Rainbow slid inside.

She groaned as her length was enveloped in tight, rippling heat. Twilight’s pussy clamped down around her, sucking her deeper inside and squeezing with a wet squelch. The tightness that had initially held her at bay now held her inside, keeping her from pulling out.

Not that she’d ever want to. Rainbow had often wondered why stallions always seemed to think with their dicks, and now she knew. Being buried balls deep in a moaning mare’s winking pussy was the most amazing thing she’d ever felt, and in that moment she decided—she wanted nothing more than to walk the streets of Ponyville with her new cock and buck every mare she saw.

She was drawn from her thoughts by a plaintive moan from Twilight. Rainbow looked down to see the alicorn shuddering beneath her, her pupils turned to shimmering pink hearts and her tongue lolling out in breathless ecstasy.

“Ohh, yes,” Twilight squealed, relaxing into the floor. “Celestia, yes, don’t stop!”

Rainbow’s mouth hung open as she pulled out, watching the way Twilight’s pussy stretched and clung to her length. Twilight moaned, grinding back into her, lower lips swallowing her back up before slapping against her groin with a wet smack.

Twilight began to work her hips in earnest, falling into a steady rhythm. She whimpered and groaned, pressing her face against the floor as she speared herself on Rainbow’s cock. Rainbow flared her wings and leaned forwards, struggling to keep her balance as Twilight’s hips slammed into her harder and harder, both overwhelming her with pleasure and driving her backwards with the sheer force behind them.

But it was impossible for Rainbow to focus past the sensations rocking her body. Twilight’s clit poking out to plant wet kisses on her balls each time she hilted, her tunnel squeezing around the base of her shaft like a vice before rippling all along her length, the brief tightening around the head of her cock before Twilight would relax, opening herself up so she could take Rainbow deep into her once more with ease, the hot wetness that splattered against Rainbow’s legs and dripped down to pool beneath them with each of Twilight’s lustful winks—each second brought with it new, wondrous bliss, and finally Rainbow gave in, crying out as she fell onto her back.

Twilight didn’t miss a beat. She threw her weight back as Rainbow fell, following her down. Rainbow’s cock never flew free of Twilight’s lustful embrace—by the time she hit the ground, Twilight was already settling back into her rhythm, gyrating atop her with loud moans.

Rainbow’s eyes screwed up as she twitched helplessly under the alicorn’s assault, the unfamiliar sensation of the pressure in her balls intensifying with every wet slap of their bodies. The little knot of pleasure started in the base of her shaft and jumped an inch higher each time Twilight dragged herself up to Rainbow’s tip, almost as if it was being sucked out of her by the slick grip of Twilight’s marehood. Rainbow gasped, hooves flying out to hold onto Twilight’s flanks in a desperate attempt to ground herself, but the other mare was relentless. Now that there was solid crystal beneath them, Twilight was free to slam herself into Rainbow’s lap with all the force of an alicorn lost in the throes of lust, driving Rainbow’s breath out of her lungs.

Rainbow’s orgasm came as a surprise. One second she was clenching her jaw and wincing from the ferocity of Twilight’s bucking, and then suddenly the dam inside her broke, the little knot hovering at the tip of her cock exploding into a wave of ecstasy. She groaned, arching her back and thrusting wildly, holding Twilight’s winking marehood flush against herself as she pumped out a jet of thick, creamy cum. Twilight let out a shuddering cry of her own, her whole body going stiff and her pussy squeezing and milking at Rainbow’s shaft as a flood of marecum leaked past the tight seal of her lower lips, the warm fluid dripping around Rainbow’s thighs to pool on the floor beneath them.

And she just kept coming. Rainbow lost track after the second shot, her mind going blank as she surrendered herself to the rapture of her first male orgasm. All she could think about was the overwhelming need to breed the mare wrapped around her rod, to pump more and more cum into the wet, muscular tunnel that drank it up with insatiable thirst. Her heart pounded against her chest and her ears began to ring, and when she was finally able to form coherent thoughts again she slumped down against the floor with an exhausted sigh, groaning from the steadily slowing aftershocks that rocked her body.

“Buck,” she breathed, staring up at the ceiling. “That was…”

“Orgasmic,” Twilight finished with a dopey giggle. She let out a contented hum, slowly rocking her hips around Rainbow’s softening member.

“Ah! H-hold up, that’s sensitive!” Rainbow winced, trying to hold Twilight still. “Hey, c-can you like, stop?”

Rainbow’s cock slipped out of Twilight’s pussy with a lewd slurp. The alicorn sighed, looking back with those strange heart-eyes as their mixed cum dripped out of her swollen marehood. “Is there anything else I can do for you, Rainbow Dash?”

Rainbow grimaced. She was no mage—the extent of her magic knowledge could be summed up on the back of one hoof—but even she could tell that this wasn’t normal. Twilight was always so reserved about sex, and even if Rainbow liked to join in when the rest of the girls started gossiping about stallions, she was never the first one to bring it up. And yet here she was, the cool crystal floor of Twilight’s castle already warming from her body heat, a thin sheen of sweat clinging to her coat and a thick stream of spunk dripping onto her lap from Twilight’s twitching twat.

That spell had done something to her.

Like, besides giving her a dick.

“Twilight? Rainbow? Are you two okay in there?”

Rainbow stiffened at the sound of Starlight Glimmer calling to them from out in the hall. “Oh, buck!” She pushed Twilight off of her and jumped to her hooves, running for the window. She just had to get out into the sky and get some space to think about this, maybe go to Rarity and see if she knew what was up. Oh, Celestia, how did these windows work? Did they even open?

She froze as the door clicked behind her. She turned slowly, meeting Starlight’s eyes with a nervous smile. “Hey, yo, Starlight. W-what’s up?”

Starlight frowned. She looked first to Rainbow, then to Twilight cooing and giggling to herself on the floor, then the growing puddle of cum under her, and finally between Rainbow’s legs. Rainbow grimaced, quickly turning sideways to try and hide her new stallionhood.

“Rainbow Dash,” Starlight said carefully. “What’s going on here?”

Author's Note

Commissioned by superfun!

Like our style? Hit us up! We'll write anything that doesn't involve feces, and draw anything that doesn't involve feces or feet!