The more Rainbow Dash thought about it, the more convinced she became that something hadn't been quite right about Twilight lately. Normally the unexplainably juicy™ duo were the closest of dear, sweet friends, but as of recent times Twi had been secreting herself to her room more often, oftentimes sighing loudly and, worst of all, being a moody little marefriend. And don't even get started on her locking herself up in the bathroom for hours at a time when Rainbow desperately needed to pee! It was just, like, absolutely the worst!
Under any other circumstances, William would've been around to take care of it, but their mutual lover had left on a business trip to Celestia-knew-where last week... So Rainbow Dash was just gonna have to slap on her sleuthing hat and get to the bottom of this. She'd have Twilight ship-shape in no time, and make sure when their hunky buddy returned, it was to a pair of grinning, high-spirited ponies.
First things first, Dash had to gather intel on the situation. She lowered herself onto her toned, tight belly, sank her hooves into the plush carpet and began stealthily creeping her way through the house's hallways. Twilight was in the living room right now, probably watching another one of her law shows or sitcoms, and it was the perfect opportunity for a sneak peek.
Red hair peeked over the top of the couch. It was followed by orange hair, then blonde hair, which was followed by a cloud-kicker most cerulean. Dash's eyes were narrowed to suspect slits, her jaw set and grinning like a madmare.
She zeroed in on the purple bookworm, all innocently laid out on the floor on top of a big, fluffy white pillow and kicking her hooves in the air. Totally unwitting about the surveillance lockdown she was now under. Nothing would escape Dash's eagle eye.
Twilight was fresh from the shower, meaning her mane was piled up on top of her bonce and wrapped up in a fluffy white towel. She was wearing an equally fluffy pink bathrobe with white trim that William had ordered custom-made for her. It looked cute.
Really cute.
Actually, Dashy had noticed Twilight had been getting into wearing human clothing more. She was adapting to her new environment, and not just out of an altruistic desire to fit in. Oh yes, Rainbow had seen all those pervy costumes laying around both Twilight and William's rooms.
A pony-sized business suit with ensemble pencil-skirt. Just perfect for taking some dictation... Or, gasp!, just dick! A pony-sized sailor fuku school uniform, for when it was "tutor time." Even a pony-sized French Maid uniform! It boggled the mind, and that wasn't even getting into things like those leather garments she’d found, or the riding crops Twilight wielded so deftly between her teeth.
What a bunch of pervs! Rainbow couldn't imagine why William had never asked her to do any of that sort of thing... Most of their play revolved around her bullying him with her butthole, or squishing his face under her blueberry-flavoured marshmallow behind, but, like, she could prooobably do that dumb dress-up stuff too!
Actually, wasn't it kinda weird that Twilight was still geeking out over human clothes, even though William had been out of the house all week? It wasn't like he was here to be impressed by her diligence.
The plot thickened!
With her hind legs out behind her and Twilight's hooves drawing lazy circles in the air, Little Miss Lavender's hindquarters were completely exposed.Her ribald bubble booty waggled as she was totally absorbed in her viewscreen show. She was watching something about a hunky crime-solving detective and his babelicious, perfectly-coiffed female assistant, who had a habit of hanging on just about every single thing the guy said. Rainbow flittered to a second vantage point to get a better look and almost gasped at what she saw.
Twilight was looking at the human man on the screen with a dreamy expression! Her love-struck eyes were throbbing and her mouth was slightly open. “Geez, Twilight,” thought Rainbow. “Get a grip!”
Twilight turned onto her side abruptly, shifting on the pillow. A moment later and the tiny equine was slowly and carefully moving her buttocks back and forth along a pillow, scuffing it under her backside. Rainbow Dash narrowed her eyes a little more and crept closer.
The view from behind was exactly what Rainbow knew it would be. Twilight had shifted her dressing gown aside slightly, opening up the pink lips of her peach. Her legs were laid out completely, knees tucked inwards tightly to squeeze the pillow. Her buttocks were clenched tightly. And her pussy was getting some serious action with Mr. Pillow! Twilight was grinding on the fluffy headrest like crazy, teasing herself silly. She started out panting, but soon stopped so she could grip the pillow tight between her teeth and hold it in place. Once that was done, she could hump with impunity.
The bookworm raised her chubby butt slightly, flashing an incriminating trail of clear liquid that connected pony to pillow. She changed her angle and really started going at it. One shake of her butt too many sealed the deal, and her towel slipped off her head, wet mane spilling down around her shoulders. The sight alone was enough to have RBD's lady-boner at half-mast almost instantly.
Dashy looked like a deer caught in headlights. What the hay! Twilight was getting off to some goofball Private Eye! He wasn't even, like, in the buff or anything, just standin' around solving crimes! Geez!
Rainbow was about to retreat, head full of new, unsettling thoughts, when she heard Twilight's voice, clear as day, "W-William... Nnnn!"
---
Rainbow stalked away, using the distraction to go and find one of the many computer terminals dotted about the house. “Computer! Hey, computer! Wake up!”
The pony straightened her back out and stood triumphantly with her legs apart as she summoned up Princess Celestia. Rainbow was ready to get to the bottom of this mystery. Once the familiar bright white glowing light solidified into her partner in crime, she could get on with the plotting and the scheming of a lifetime. She was just about rubbing her hooves together in glee.
The only problem with the whole thing was that said bright white glowing light wasn’t appearing at all! Let alone anything about it turning into an equally bright and glowing white Alicorn. In fact, very little of anything at all was happening.
Rainbow Dash moved closer to the monitor, placing her hooves on the underside and peeking over the top of them. “What the...”
In the magical fanfare’s place, there was instead a midnight blue snout positioned level with her own. With nostrils most fiercely flared, it was peeking out of the edge of the screen, as if emerging from within. The space where the twitching snout was neatly segmented by the screen was filled with a thick cloud of blackest smoke.
The equine schnozz shifted forwards suddenly, with enough suddenness to startle Dash into tumbling back onto her thick hindquarters. She watched as its owner began to force their way through the screen, head-first. A perfectly set blue mane, speckled with a million stars, forced its way through the tiny screen. As soon as the cramped locks were through, they immediately cascaded out to their full length, spilling halfway down the wall. A familiar large purple horn and green eyes filled with eternal wisdom rounded out the features of Princess Luna.
The Alicorn’s head was now, disconcertingly, jutting out of the wall. She wiggled her neck a little as she sought more breathing room, then sighed as she realized this was as good as it got. “Fie on thee! For what purpose hast thou disturbed the Royal storytimes?”
Rainbow Dash tried to peer around Luna’s visage to peek into the depths of the monitor’s display. She cocked her head and pointed with a hoof. “Is Celestia in there?”
“With the onset of the witching hour, our sister hast set her head to rest. In her absence, the Princess of the Night keeps silent vigil over this household!”
“But she’s an AI! And so are you; you don’t sleep.” fumed Rainbow.
“Fie on thee a second t - “ began Luna, but Rainbow butted in before she could really launch into a proper diatribe.
Well, look, I just need to talk to Celestia about why Twilight’s acting so funny lately. Can you wake her up? For just a second?”
“We shan’t! Whatever the problem is with your beloved Lady Sparkle, it may wait until the master’s return!”
Rainbow crossed her eyes. This wasn’t getting her anywhere. She was just about to give up and wander back to her bed for a well-deserved rest, when a “Settings” bar displayed below Luna’s face caught her attention.
“What does that do?”
“It does nothing, aside from perhaps endanger the lives of irresponsible little ponies! You wouldst doubtless explode the moment you touched it, reckless pega - “
“Boop.”
As Rainbow Dash withdrew her hoof, a holographic display shot up in front of Luna’s face, bearing a variety of interesting-looking settings like “Picture Mode”, “Screen Adjustment” and “Time Zone.” While Rainbow was studying that last one, Luna poked her tongue out, rather hopefully attempting to stretch it towards the “X” switch in the top-right corner.
“What if I asked you about Twilight innnnn... ummmmm... Germany? No, France! Boop!”
As Rainbow Dash depressed the button, Luna’s scowling face melted away. At this moment, it was daytime in that far-off country, and the night’s keeper found herself replaced in seconds by a yawning Princess Celestia.
The rainbow-maned Goddess slipped out of the screen with a practised ease her sister couldn’t quite replicate, stretching her long legs out. She glanced outside at the black sky, then back to Rainbow Dash.
“Qu'est-ce qui se passe?” she asked, tilting her head slightly.
She trotted in a circle, tossed her mane, then gave Rainbow another confused look. “Pourquoi il fait noir dehors?”
Rainbow frowned extra hard. She fiddled with the controls a little more, while Celestia watched with a bemused, yet delighted, smile.
“How about now?” she asked, glancing back to the princess.
“Whatever are you doing, Rainbow?” Celestia inquired, in-between shaking with laughter.
Rainbow leaned back against the wall with a relieved sigh. “It’s about Twilight. You gotta help me!”
Celestia settled gently to lay on the carpet, tucking her legs beneath her barrel. “Ahh, yes, my dear pupil. She has been rather moody lately, hasn’t she?”
“Yeah! Like, what’s the deal, Sunbutt?”
“Sunbutt!” remarked Celestia, completely taken aback. The most refined ruler’s mouth was hanging open in shock. “Why would you call me...”
She tossed her head this way and that, before her eyes finally alighted on the blazing, honeyed flare adorning her flank. “Oh. Oh. Oh, We see how it is.”
“Aww, come on, don’t be a sourpuss!”
“I was not being a sou - “
“Listen, all I need to know is what’s wrong with Twi so I can fix her! Just tell me what I gotta do.”
Celestia tutted. "I'm not sure there's anything you can do, Rainbow. Twilight is simply feeling a little bit lovesick following William's absence."
"Ohhh, I get it!" exclaimed Rainbow, slapping one hoof down onto the other. "So she wants the D?"
Celestia couldn't help but smile at the way the brazen filly's face lit up. "Yes, exactly, Rainbow Dash. Twilight Sparkle's thirst for a dicking advances tirelessly by the day. And with it, so too does her morose mooching."
Rainbow's eyebrows shot up as she listened to the apocalyptic proclamation with growing concern. "I have to save her."
"Yes, you must succeed at this task. It must be you and you alone who ultimately assists Twilight Sparkle in doing what needs to be done. Do you understand?"
"Yes!"
Celestia nodded sagely. "Then go. There is no time to lose."
"You're right!"
Rainbow Dash struck a pose right there in the middle of the room, standing on her hindlegs. One hoof was resting on her hip joint, the other triumphantly thrust into the air. "Pony Penis Powers... Activate!"
There was a long moment of baited breath, during which Princess Celestia's hoof found its way to her forehead. Rainbow was just about to loudly voice her complaints about the current horsecock-less state of the universe, when her entire body reeled.
"Uhooooo!" cried the pegasus, a moment before she thrown off her hind-legs and down onto the hard floorboards below. Her oversized pony caboose absorbed all of the impact like a sponge, but in the absence of any pain, she had a completely different sensation to cope with! Something hard and firm was growing inside of her, trying to make its way directly out of her pelvis. The blue pony squirmed and writhed, crying out as unfamiliar sensations surged through her small frame.
"Wah! Hold on! Too fast!" An expanding, blue-fleshed nub had sprouted between her hind-legs. She threw her legs back and stared at the ceiling, both forelegs cupped over her groin as something struggled under them to make its presence known. "I'm not ready to abandon my marehood just yet! Wait a second!"
However, her new thigh-slapper had no intention of being denied. As she watched, a federal blue equine member sprung out so rapidly it threw her groin-cupping limbs aside. The shaft quickly bolted upwards, racing towards the ceiling and casting a long shadow over Dashy’s face in the process.
Dashy arched her back, yowled cutely, and made one of the most undignified faces of her life. Which was saying something for her!
When the cock storm had passed, Rainbow heaved a great sigh. The tension along the pegasi's spine faded and she flopped back onto the floor, limp as overcooked spaghetti. She trembled, unsure whether to giggle or cry, brain struggling to keep up with a feeling similar to the female orgasm, but at the same time strikingly different. A trembling, quivering boy-orgasm. She dropped her eyes to the space between her legs.
“Holy crackers!” thought Rainbow Dash. “What a plus-sized horse-weiner!”
She'd seen some big-uns back in Equestria for sure, some real Cake-takers here and there, and this was definitely on the upper-end of the scale. Not quite a patch on William's, but given she was just above knee-high on her boyfriend and cum-tank, that was kiiinda to be expected! It looked ruthlessly hard and intimidating, with a gigantic flared head that would do a number on anypony who got it near, along with some big sloshin' nuts on the underside. Her normally so flush-lipped pussy was nowhere to be seen, as if afraid for its own sanctity around such a heapin' helping of mega-cock. She placed both her forehooves on her new member and grinned goofily as she rubbed up and down the shaft.
"Ooooooh. Rainbow likey."
Celestia uncovered her eyes. "My goodness. Don't you think that's a little large to be putting inside her?" She hardly paid attention to their love-lives, or she'd know they’d both taken larger plenty of times.
Still laying on her back, Rainbow grinned at the Princess over the top of her newly-grown pole. "Hey! She's really upset, okay?"
---
Some prowling around the house later, during which Rainbow's new endowment slapped the insides of her thighs so many times she thought it would be bruised by tomorrow, the pony finally stumbled upon her prey in a secluded corner of the house. Twilight was sitting on all fours on a swivel chair before one of the house's many computer terminals, one hoof quietly tack-tack-tacking away at the keyboard before her. She was still wearing her fluffy pink bathrobe, not having bothered to change. Even when William wasn't around, she just kept right on wearing clothes.
A page about Bio-Droid Laws and Regulations was up on the screen. Twilight was making notes on a small tablet sitting by the keyboard. When she wasn't writing, the pony made a point of holding the digital pen in her mouth, giving it quite the hardcore sucking as it filled in for the preferred object she'd much rather be holding inside her cheeks.
Suddenly, and without any warning, Rainbow crept up behind her, gripped the chair with both forelegs and spun it around! She turned it a bit harder than she intended, however, and the chair rocked from side to side before abruptly depositing a shocked Miss Sparkle right on top of her.
Crash! The pair ended up in a heap on the floor.
Twilight groaned, rubbing her forehead, and slowly began to get up. Her hoof came down on something she didn't remember being there earlier. "Oohoo, Rainbow... What's this?"
She brought her face closer to the large, twitching equine shaft, eyes and mouth both watering-up at the sight of it. "Mmmmn... Wait, no, seriously. What is this?"
Twilight had been with William plenty over the last few months, but her sexual experience with other partners was still only just blooming. Rainbow's pheromone cock-scent had her eyes watering and her pussy itching so badly. She wasn't used to this from her friend one bit, and her normally-controlled demeanor became impossible to keep up. Her hips squirmed side to side, knees pressing together. Her poor, neglected booty was tingling and making her act strange.
"Mmmm, mmm. Where did you get this, Rainbow? Oooh, oohh..." She drew a hoof along Rainbow’s member, biting her lower lip. Her eye contact with Rainbow Dash was broken whenever she glanced down at that veiny, powerful she-cock.
Rainbow's eyes lit up right away. Twilight's depression was sloughing off of her, replaced by hot, fun arousal. And something about that starry-eyed look in the bookworm's eyes made her feel especially smug. Rainbow knew right then and there that she wouldn't be happy until she'd tried out her new member, ejaculating deep inside her cute friend Twilight Sparkle.
Her tongue made another circuit of her mouth as she leaned closer. "Big, isn't it? Awesome, isn't it? I bet you can't wait to get on it, huh Twilight?"
She might tease Twilight for being a cock-addict, but at the same time Rainbow was crazy about getting her dick up Twilight’s ass! It was impossible to even entertain thoughts of her meaty cock being soft, as long as she was around Twilight and thinking about stuffing her member somewhere warm and receptive. Rainbow was suddenly seeing Twi less like her best friend and more like a hot pony babe who had her cock red-hot!
The pegasi dusted herself down and climbed to her hooves, smirking inwardly as she stalked around Twilight in a circle. The overworked and sex-deprived brainiac's eyes molested her member every step of the way. Dashy wouldn't have said so in front of William, but she felt like the big man of the house right then, able to do whatever she wanted with this cute filly and get away with it! Having a cock was kinda awesome, why hadn't she done this sooner?
She moved behind the sweating, panting Alicorn, reaching for the sash of Twilight’s bathrobe. Rainbow vigorously untied it and threw the robe open. Twilight gasped as her clothes were pulled away, rendered half-naked by Rainbow's grabbing hooves. Even for ponies who normally went naked, there was something undeniably carnal about her heaving purple chest being suddenly exposed! The act itself, the freeing of her bare skin from her clothes, made her feel truly exposed, reactively shrinking away to hide her lewd and vulnerable body.
She groaned into Twilight's ear, "You miss William, right, Twili? How about I jam something big and fat in your ass? That’ll do the trick!”
Twilight couldn't help herself, her ass backing up and rubbing on that hot dick in circles. It got under her robe and she rubbed bare flesh against against the great big cock, making sticky precum fire across her back. Her body that normally felt so ordinary and comfortable naked now felt burning-hot under Rainbow's perverted gaze! "Haah... Haah... My body's so hot... But..."
Rainbow leaned closer. “I can help with that... You can lick it alllll day long."
Twilight chewed her lip nervously. "I'll wait for William! I really should wait."
Despite Twilight’s weak attempts to stay a good girl, she slipped her robe off the rest of her way as Rainbow watched, letting the pegasus leer at her how she liked. She took the shoulders in her hooves and shimmied her ass side-to-side, getting that pesky thing out of the way of her molten-hot, needy body. Rainbow let out a sweet, musical cry as that huge nerd butt glanced on the stiff shaft of her cock.
Dashy was relentless. She wanted to help Twi, and she wanted to help herself. "Come onnn, Twilight! I grew this big thing just to make you feel better while he's gone! Just lemme put it in you for a few seconds!”
“If you don't like it, I'll take it out~ Promise!" Rainbow continued to goad her. She was dripping enough precum that the head of her cock was soaking in it. She'd pump out litres of semen if given the chance! She'd soak this prim and proper faithful pony maiden in her spunk.
Dashy turned her pony chum's head just enough so she could see her clearly. "Come onnnn."
She looked down at Twilight's chubby, plump butt and her eyes misted over with lust. "Shake it! I want to see you wiggle this big bottom for me."
Twilight looked back with teary eyes and a little helpless pout. "Ahhh... Alright, Rainbow..."
The purple pony spread her legs a little bit, trying to get good footing. Her naked ass stuck out behind her, waist turning awkwardly at first, but her sexual behaviors took over her movements shortly. Soon Twilight’s body was swaying like a world-class stripper. She showed the best features of her curvy body, enticing that cock with the sluttiest gyrations. Twilight looked over her shoulder with an uncharacteristic alluring expression, violet eyes half-lidded, making a teasing kissy face toward her best friend. She was really putting on a good show!
Twilight's eyes hooded seductively, her tongue occasionally escaping from her mouth to accompany a little wink. She might be a prude on the outside, but inside she was a truly seductive little dick-milker, thirsting for juice.
The lovestruck sporty pony gave Twilight a divine smile as she crowded into the space between them. She looked so uncharacteristically seductive, strutting over to her with one hoof in front of the other. "Oooh~ I want to fuck right now! I want to bully this over-sensitive pucker!”
Rainbow Dash danced her hooves around Twilight's fat ass, then slowly raised one over her head. She let it linger there as she braced herself to spank her friend’s big fat flank.
That big butt had to be punished, and the speedster’s expression immediately changed to that of a teasing pervert as she did exactly that. Now that she was done marvelling at the sheer size of Twilight’s caboose, she got down to work. She brought her hoof down onto Twilight's jiggling behind, and there there was a loud crack as her hoof connected with that fat ass. Rainbow’s soft smile turned wicked as she struck Twilight's wobbling bottom again and again, until the poor pony's face was red and heated.
"How's this?" she said, rubbing Twi's big, sore bottom.
"Hyaaahhh, nnnnnooooo!" Twilight's eyes rolled back for a half-second every time her bottom was swatted. Her poor purple ass was getting red, the sharp sensation maxing out her sexual response. Her pussy was steaming, wetness bubbling down her thighs, her mind foggy with extreme levels of lust that she couldn't bear.
"Ahuaaahhh... Rainbow, I, uhhhnnnn..." Twilight wanted to voice some kind of resistance. This wasn't helping her cope with missing William! This was mistreatment by a perverted devil with a drooling cock. But poor Twilight was too dizzy to do much more than whine. She pressed her body backwards on top of that cock, bringing a fleshy and throbbing ponut right up to the tip. With a single lengthy and drawn-out grind, Twilight Sparkle enveloped the steamy member to the base in her piping-hot, squeezing asshole.
It was a credit to Rainbow that she didn't lose her composure. As that juicy anus backed up onto her gigantic stiffy, that smug smile never left her face. She gripped Twilight's thick behind in both hooves, only releasing her whenever she wanted to give her a loud crack across the hindquarters. Which was often!
Twilight trembled and cried out as Rainbow Dash's cock got deeper and deeper into her tight, flexible butthole. When her legs completely gave out, hooves splayed out across the floor, Rainbow was quick to straddle her. She got the brainiac to bear her whole weight as she thrusted all the way inside, driving the anal sex-addict wild.
Once Dashy was on top and thrusting, she could really tighten those lean haunches of hers. Each curl of her back sank her marvelously black-sheathed member deep into her friend's extremely-developed backdoor. There was no mercy from a behind like this! Each thrust into Twilight's core made Rainbow's brand-new member tingle, that warm and supple sleeve gripping her tight as a glove. Twilight's butt pulled on her, and each time she drew out was a struggle to not just pump her gushing semen deep inside her best friend.
Twilight's mind looked like it was far away. Under those forelocks that lightly-wavered with each thrust, her eyes were hooded, mouth hanging open. Her red tongue was stuck out at an odd angle. The only sign she was still with her friend mentally was one that made Rainbow almost squeal out of its sheer cuteness: when Dashy put her hooves on either side of Twilight's shoulders and redoubled her thrusting, purple hooves wrapped around her forelegs. They gripped her legs tightly and pulled her cock deeper. It made Rainbow’s heart soar so much she felt ready to shoot off right then and there.
Rainbow squatted down behind the drooling, eye-rolling pony named Twilight Sparkle. She slid her fat cock in and out of her cute little friend, and with each hump into her, she came a little more. She lost track of how many times she fired off, how many times she wrung her seed out into Twi. She came so much, and unloaded her thick mare cream inside Twi’s ass so many times, that each new torrent of ejaculation pumped the previous one out. Each tremble of her cock was accompanied by an oozing creampie running down Twilight's pussy and joining the growing puddle on the carpet.
Despite this, Rainbow continued to saw her huge horsecock back and forth. Her dangling black nutsack continued to tense up over and over. When she was finally done cumming, Rainbow pulled Twi back into her lap, bouncing her up and down a few times to get her nice and settled in place before running her tongue up her cheek. "Heheheh."
She paused her thrusting and forced Twilight all the way down her cock. Still keeping her squirming, groaning friend in her lap, disregarding Twilight's little kicks and protests, Rainbow began moving her cock in circles inside that tight butthole. Gloopy blobs of semen from her previous ejaculations were dripping down Twilight’s ass and joining what was already soaking into the carpet! "Incredible... Mm, Twilight's body is incredible!"
Rainbow could have kept going... But it looked like their private time had come to an end. She froze when she heard the front door shutting at the other end of the house, knowing it could only mean one thing.
William was home, and he was about to find Rainbow balls-deep in one of his favourite pony buttholes.