Twilight Sparkle's Stiffest Wingboner

by GaryOak

First published

[F/F] Twilight has wing priapism, more commonly known as the chronic wingboner, and Princess Celestia is the only pony who can help her find the relief she so desperately needs.

Twilight has been Equestria's newest Princess for a week. After a grueling day of royal duties, she prepares to unwind in the only way she knows: curling up with a good book. Unbeknownst to the young alicorn, a book mix-up leads to wing priapism, more commonly known as the chronic wingboner.

As her own sexual desires threaten to enslave her, she reaches out to Princess Celestia, the only pony who can help her.

[F/F]

Edited by Horse Voice.

Twilight Sparkle's Stiffest Wingboner

View Online

Twilight Sparkle's golden hoofguards clanked against the library's wooden floor as she discarded them and massaged her forehooves gingerly. She exhaled loudly as she took a few wobbly steps toward her bed before flopping down on it.

“Being a Princess is so much tougher than it looks,” she said, laying on her back.

She closed her eyes and took a deep breath. The library was deserted; Spike had left to check up on Rarity as she put the finishing touches on a dress “fit for our most fabulous Princess,” as she put it. Exhaustion made Twilight's limbs feel sluggish and heavy. As if magnetically drawn, she mechanically rose to her hooves and plodded downstairs in search of a good book to fall asleep to.

Her eyes scanned the shelves. It needed to be the perfect book – something compelling. The past week had left her head so full of new information, stress, and duties, that she desired a more recreational read. She needed a break.

Twilight perked up. “Oh, I know!”

The clacking of her hooves on wood filled the library as she trotted toward a book resting on a chair near the door. It was a new Daring Do novel, released that month. Rainbow Dash had lent it to Twilight three or four days ago as something to take her mind off things, but it had since been forgotten.

Twilight's horn shimmered as she pulled the book toward her. “Daring Do and the Jungle of Terror?” She rubbed her muzzle. “I'm sure Rainbow told me the new book's title was Daring Do and the Alicorn Amulet.”

Shrugging, she flew upstairs, and landed none-too-gracefully on her bed. She was still getting used to her new appendages. She curled up and cracked the book open. A frown adorned her muzzle as she began to read.

“This is messy hoofwriting... how come this isn't properly printed like all the other Daring Do stories?”

Too weary to be bothered enough to stop reading, she continued. Her mouth opened wider and wider with the turn of each page. “By Celestia!” She raised a hoof to her muzzle when she came to a scene depicting Daring entrapped by a vine monster that plunged a half-dozen of its thick appendages into her marehood.

“Wait a second, I recognize this hoofwriting!” She narrowed her eyes. “Rainbow... how could you write something like this?”

But instead of tossing the volume aside, she pressed on through page after page. Whether it was the writing, her weariness, or morbid curiosity, she did not know. Before long, she began to feel a tingling in her nethers. Soon, the urge became too powerful. She bit her lower lip and unconsciously reached for her dripping fillyhood with a forehoof.

“Aaah!”

Pleasure surged throughout her body as her nerve endings flared from her hoof's gentle touch. She moaned again as she began to rub herself with one forehoof and turn pages with the other. Her eyes moved at a blazing speed as she burned through sentence after seductive sentence. She giggled as Daring, lost in her orgasms, was saved by a heroic Rainbow Dash, who sliced the vine monster to ribbons with a series of stunning aerial maneuvers.

“Of course you'd write yourself in – oh my...”

Twilight could not help but employ her other forehoof to assist in stimulating her winking pussy. As she read a vividly-written scene of Rainbow performing expert cunnilingus on her fantasy lover, a pool of Twilight's filly fluid began to accumulate on the bed and soak into the sheets. Forced to use her magic to continue turning the pages, she read on.

“Oh, Rainbow, it's just like I'm Daring Do right now!” She whinnied as her forehooves massaged her g-spot. “You are so good!”

A pomf filled the air as her wings flared to their full width. She giggled mischievously, and worked her forehooves harder and faster as Rainbow and Daring's pleasure mounted ever higher. Her breathing became ragged and husky as the story – and Twilight – neared their climaxes. Twilight's hips bucked on her forehooves as Rainbow and Daring scissored while sharing a deep, passionate kiss.

And then they came. And so did Twilight.

A bomb of pure pony pleasure burst within; endorphins coursed through her as her orgasm claimed her consciousness. A flood of her juices spilled forth from her nethers, washed over her forehooves, and soaked the mattress. Her wings remained painfully unfurled. Fatigue mercilessly slammed into her as her orgasm petered out. It felt like her body weighed ten times its normal amount, and as soon as her head fell atop the book responsible for her wild ride of pleasure, sleep began to take hold.

“I – I never knew you could write this vividly, Rainbow...” Her wings gave another painful throb as she blacked out.

* * *

“Twilight? Twilight! You alright?”

The words swam around in Twilight's head. She cracked a heavy eyelid open, and pain shot through her skull. She had hoped to wake up at a time when the sun was not bursting through the window onto her bed. As the room swam into focus, she saw Spike, who held an elaborately wrapped box bearing Rarity's cutie mark.

“Uh, Twilight? Have you been up all night studying Princess stuff again?” said Spike, eyeing the erotic book her head rested on as he set the box down. “Whew. What's that smell?”

Twilight hastily raised her head and snapped the book shut. “Uh, it's nothing, don't worry about it.”

Spike held his nose as he stared at the spot in the bed surrounding where her flank rested. “Did... did you wet the bed? It looks all damp...”

Blushing, Twilight scrambled to her hooves and hurried Spike downstairs. “I said, don't worry about it!” As awareness returned in full, a deep, burning lust in her marehood made its presence painfully apparent.

“Okay, okay, jeez!” He raised his hands as he nearly toppled down the stairs. When they reached the ground floor, he turned around and prodded her right wing. “Say, Twilight, are your wings alright? They were like this when I found you sleeping.”

A sharp gasp escaped her lips. “Oh no! I've read about this! Oh no, oh no, oh no, what'll I do?” she said as she darted around the room, trying to find a book of some kind. Her pussy lips trembled more with each passing moment.

Spike clapped his head in his hands. “Is something wrong? What's wrong? What can I do?”

Twilight's blush deepened when she noticed a dribble of her mare love juice clearly marking her progress through the library like hoofprints in the snow. “I think... I think I'm suffering from wing priapism...”

“Wing pria... pria-what?” Spike scratched his head.

Twilight's hooves shuffled around as she averted her gaze from him. After a long moment of trying to devise a delicate way of putting it, she said, “Uh, more colloquially... it's known as a wingboner... A... really bad one...”

A few seconds had passed before Spike's face lit up like one of her study lanterns. “Oh. OH! I see!” He failed to suppress a loud chortle. “Rainbow Dash told me she had one of those once. You need to see a specialist. Luckily, there's one in Ponyville named... Panacea, I think.”

She rushed to his side, kneeling before him. “No way! Please, please don't tell anypony about this! It's... just unbecoming of a Princess to have to suffer from this!”

“But, you can't fly like that, can you?”

Twilight pouted. “No, I can't. They won't budge, and they kind of hurt.”

Spike looked skyward, scratching his chin. “Well, I suppose you could ask Princess Celestia...”

Twilight leapt four feet into the air. “Of course! If anypony can help, she can!”

“I wonder if she's had this problem before...” said Spike with a snicker.

“Spike!”

Spike cringed as he ran to pick up a scroll and ink. “Okay, okay, I was just kidding!”

Twilight winced and let out a muffled, strangled moan as her aching pussy sent its silent cry of desire throughout her body. The urge to pleasure herself once more grew overpowering. “Quickly, take a note!” she said, panting.

Spike dipped the quill into an ink pot. “Right!”

“Dear Princess Celestia,” said Twilight, speaking so quickly her words jumbled together. “Last night I suffered a severe case of wing priapism. I'm afraid to see a doctor about it, because, well... it's embarrassing! What if everypony finds out? I don't know what to do. Will you help? Still your faithful student, Twilight Sparkle.”

“P-i-r-a... p... uh...”

Twilight's ears flattened as she let out a panicked snort. “P-r-i-a-p-i-s-m! Hurry up, Spike!”

As the sound of furious scribbling filled the room, another powerful wave of lust hit her. Her horn shimmered. Using the last of her concentration, and she fashioned a glowing magenta dildo with her magic. She lifted her tail, took careful aim, and thrust the shape into her gaping maregina.

Although the magical aphrodisiac was nearly as thick as her forehoof, her hungry, winking pussy devoured it with ease. She closed her eyes and grit her teeth, fighting the urge to whinny from the stimulation. Inch after inch slid in, until all fourteen were buried safely inside. She lowered her tail and pressed it against her open love tunnel just as Spike triumphantly declared, “All done!”

“Good, very good,” she said sheepishly, opening her eyes. She knew she could take more than what she gave herself, but she wanted to leave a few inches of wiggle room to work with. And work with them she did; she slowly slid the dildo back and forth inside, the steady stimulation sating her newfound addiction enough to allow her to think straight once more. “Send the letter!”

“Will do!” Spike heaved and loosed a great belch of green flame, and the scroll vanished. “Say, Twilight, what's with the magic?”

Twilight giggled. “Oh, what, this?” She pawed at the ground. “It's a... a spell that I'm trying as a temporary solution for my priapism.”

Spike sniffed. Twilight's alicorn arousal aroma permeated the air. “It's just like the smell on your bed... are you sure you're alright, Twilight?”

Twilight's cheeks burned as she tried to pull a straight face. It was not an easy task; every few seconds, contortions of pleasure cracked her feigned mask of innocence. “I'll be fine... just as soon as Princess Celestia helps me fix this problem.”

She moved the dildo faster and faster as they conversed. Her legs wobbled as her stimulation mounted. As she stumbled backward, one of her wings knocked over a pile of scrolls stacked on a table, sending parchment everywhere.

“Twilight! What's happening to you?” As Spike rushed to her side, his right foot skidded on one of the larger puddles of her filly fertility fluid. He clutched her left foreleg, and stared up at her.

Twilight bit her lip as another surge of pleasure racked her body. “Really, Spike, don't worry! Just sit over there until the response arrives, or something. I'm getting close...”

“Close? To what?” He arched an eyebrow.

She masked a loud moan with a laugh. “Close... close to the end of the anticipated response time from the Princess!”

Releasing her, Spike walked toward the staircase. “Uh, okay, if you say so.”

The dildo within her achieved a breakneck pace; her every nerve ending fired with enough force to shake her to the core. A sense of panic blossomed in her chest. She realized that by constantly increasing the dildo's speed, she had hopped aboard the Friendship Express, bound directly for horsegasm.

Twilight tried with all her might to slow her conjured toy's reckless pace, but to her horror, found that instead of sating her intense sexual hunger, the added stimulation only increased it. For nearly five minutes, she continued to resist, but her escalating equine ecstasy eroded her willpower. Regardless of how swift Celestia's reply came, Twilight was sure she would first.

As she wondered how she was going to explain it all to Spike, she looked down and noticed a scroll that had unraveled after she knocked it from the table. Desperate, she sat on it, hoping it would absorb the inevitable tsunami of vaginal fluid. When the dildo brushed against her g-spot again, the last of her resistance failed her.

It turned out her decision to use the scroll was well-founded; wave after wave of mind-jarring pleasure crashed into her as her broth spilled out unchecked. She felt the air stripped from her lungs as she fought not to writhe from pure bliss, the likes of which she had never before felt.

Twilight's lower lip trembled as her climax reached its peak. Finally, she gave a great whinny as her orgasm's apex hit her. Fortunately for her, Spike belched loudly at that same moment, heralding the arrival of Celestia's reply. Twilight's eyes rolled madly as she felt swept off her hooves by her flagging orgasm.

“Oh, yes, yes, yes!”

“Um, Twilight? I know you must be happy about getting a response so quickly, but I've never seen you this happy to get a letter from the Princess!” Spike snatched the scroll out of the air. “And why is your tongue hanging out like that? Are you drooling?”

Twilight shook herself. Her climax had finally let go of her, but she felt no less aroused. In fact, she thought she felt more aroused than when she first started pleasuring herself this afternoon. “Just – just read – the letter!”

Spike unraveled the scroll and cleared his throat importantly. “My dearest Twilight, I wondered how long it would be before you had a run-in with this particular problem. Do not fret; everypony with wings experiences it several times throughout their lives, especially at a young age. The first instance can be quite terrifying. As such, I feel it is time to administer a hooves-on lesson in the matter. Meet me on your library's balcony. I shall arrive shortly. Yours, Celestia.”

No sooner had Spike finished reciting than Twilight trotted up the stairs as fast as her weary limbs would carry her. When she reached the balcony, she turned and said, “Thanks, Spike. Take care of the library while I'm gone; I'll be back in a day or two!” before she opened the door, barreled outside, and slammed it behind her.

The raw flame of lust blazed within her nethers, and incinerated the last vestiges of the relief from her latest orgasm. She writhed on the deck and massaged her quivering pussy lips with a forehoof as she worked her dildo at a blistering speed. Her eyes jammed shut as she submerged herself in pleasure, losing track of time. Every few seconds, she would whimper softly as her other senses dulled, giving way to ecstasy.

The loud clearing of a throat snapped her out of her reverie. She opened her eyes and looked up. Framed in the mid-afternoon sun, Princess Celestia, her sparkling mane bathing Twilight in its aurora of colours, beamed down at her. Twilight tried to remove her forehoof from her marehood, but the sight of her mentor only made her swish it faster. Celestia appeared to glow with a divine radiance that sex-hungry ponies could only dream of.

“P-Princess Celestia, I – I –”

Celestia raised a forehoof. “No need to explain, Princess Sparkle. Do not be ashamed; this happens to everypony.” Her eyes crinkled with love as she smiled serenely down at her passion-paralyzed student.

“But, I – ah! – I've never heard – ooh! – of it being – aah! – so bad!”

Celestia brought her raised hoof to her muzzle and tittered. “That is probably because you have not had wings until now. By the looks of it, they are merely making up for lost time.” She winked. “I may be no doctor, but by the time this night is through, I will cure you of your condition.”

Twilight tried to stand up on three legs, but fell on her stomach as another wave of pleasure floored her. “I've already climaxed twice, and it's only getting worse!”

Celestia lowered her muzzle, and touched it to Twilight's. Twilight looked up, and into her eyes. “It may not be easy, but I assure you that I will provide you with the relief you need.”

Twilight somehow willed herself to wrench her forehoof from her hungry fillyhood and nodded at Celestia. “T-thank you...”

With surprising speed, Celestia opened her mouth, wrapped it around Twilight's juice-soaked forehoof, and sucked. Every drop had been licked clean within mere moments, and Celestia withdrew. She smacked her lips as if she had just taken a nibble of an expensive piece of cake. “A procedure of this caliber must be conducted within the sanctity of my royal chambers. Since you cannot fly, you shall ride on my back to Canterlot.”

Twilight stared blankly at her now clean hoof.

“You should also end your spell,” said Celestia, eyeing Twilight's shimmering horn. “You will have use of it later, and you would be well advised to conserve your energy.”

Twilight's face turned scarlet. “But, you don't know what spell I'm –”

“Oh, I think I have a pretty good idea.” Celestia's eyes sparked as she grinned. “Withdraw it, please.”

“What?”

“Withdraw it.”

With her face feeling almost as hot as her nethers, Twilight slowly withdrew her magical sex toy. Celestia admired it with the air of Hoity Toity examining one of Rarity's latest fashion achievements.

“Fourteen inches, if I'm not mistaken?” Celestia looked to Twilight, who nodded reluctantly. “You wanted some wiggle room, I see.” She gave the shaft a long, slow lick. “Delicious. Well, my student, you have much to learn. End your spell, and climb on my back.”

Twilight obeyed. As she approached Celestia, her elder wrapped her forehooves around her. Feeling calm for the first time all day, Twilight returned her embrace. The two Princesses of Equestria nuzzled affectionately. After they rubbed their snouts together one last time, Twilight hopped on Celestia's back, curled up, and fell into a lust-filled sleep.

* * *

“You're waking up at last. Excellent.”

Twilight's eyes fluttered open. Her wings hurt immensely, but the rest of her body rested on the cushy purple sheets of Celestia's bed, and her head lay upon the long, golden pillow. Celestia herself stood before her. Her usual royal regalia was absent. Flapping her broad wings, she flew toward and landed beside Twilight. A broad smile covered her muzzle.

“Now,” said Celestia, the smallest hint of her tongue licking her lips, “we begin an important lesson in being a Princess. Perhaps the most important. As you are no doubt aware, wing priapism can dramatically disrupt your day-to-day life. The first relief is always the most difficult, but following my guidance, it should be of no further trouble.”

Twilight sat up at full attention. Her wings throbbed as her vagina's nerves screamed with unsatisfied desire. Unable to resist any longer, she attempted to plunge both forehooves into her nethers as far as they would go, but gasped when she found them bound by magical golden fetters. She looked into Celestia's eyes pleadingly.

“The time will come, my student,” purred Celestia, her horn aglow. “First, your wings must be cleaned. Have you yet done this?”

Biting her lip, Twilight shook her head. Being unable to sate her exponentially increasing lust was nothing short of torture. She gave a series of loud moans as her pussy panged for stimulation. She struggled uselessly against her mentor's magic.

“Lesson one,” said Celestia, positioning herself behind Twilight. “Preening.”

Before Twilight realized what was going on, a surge of bliss rushed through her. Turning her head to the left, Twilight gasped as she saw Celestia's muzzle buried deeply in her wing. Twilight cried out, the sound ringing off the chamber's blue walls as Celestia's tongue darted expertly between her feathers.

“Oh – oh – OH!” Twilight's hind legs scrabbled against the soft sheets. “Please, Princess, please, don't stop!”

Celestia's response was an affectionate nibble close to Twilight's wing bone. Twilight gasped as her marehood clenched at thin air. She could do nothing but succumb to her body's soaring ecstasy as Celestia meticulously licked and nibbled at every millimetre of her left wing. Just when she neared her breaking point, Celestia withdrew. She leaned forward and pecked Twilight on the muzzle.

“Now for the other one.”

Twilight felt a burning sensation where Celestia had kissed her. Her mind had little time to dwell on her blossoming feelings for her teacher, for a fresh wave of pleasure originating from her right wing threatened to wash her away. Twilight began bucking her hips against the bed, rubbing her nether lips against the juice-slick silk as Celestia started at her wingtip and slowly worked her way in.

Magenta sparks flew from her horn, and soft whinnies filled the air whenever the pleasure grew too much. Her vagina buzzed as her rigid wings sent powerful euphoric signals through her body. Pressure began to build down below. She had not climaxed with the first wing, but this time, she knew there would be no stopping it.

After what felt like an eternity, Celestia reached the base of Twilight's right wing, gave it a final bite, and withdrew. Desire eroded rationality, and Twilight spun around and lunged forward. Her muzzle locked firmly with Celestia's as she plunged her tongue into Celestia's mouth. As they both toppled over and Celestia's nimble tongue began to dance with hers, a powerful orgasm rocked her.

Twilight's juices spilled from her winking marehood, matting Celestia's coat. Every nerve ending cried out with wanton relish as Celestia's kiss swept her away. She pressed her muzzle against Celestia's hard, trying to reach as far as she could with her eager tongue.

While her tongue moved with pure genuine youthful love, Celestia's danced with a graceful, measured affection that drove Twilight wild. She grinded her pussy against Celestia's lower belly as she rode the highs of her orgasm. She moaned into Celestia's mouth as it dwindled.

Twilight regained her senses, and withdrew from their kiss. “Oh no, Princess, I'm so –”

Celestia leaned up and kissed her. “I understand, my student. We have completed the first lesson, and you have led us into lesson two.”

“You – you planned this?”

“Of course.” Celestia reached up and stroked Twilight's mane with a forehoof. “How do you feel?”

Twilight's wings remained as unresponsive as ever. She lowered her head until her muzzle was centimetres from Celestia's. Her breath came hot and ragged. “I... I want you, Princess. I want you... so badly...”

She felt her heart wrench as she spoke the shameful words. Celestia had been more like a second mother to her than anything else, and now, Twilight wanted nothing less than full intimacy with her. While her every sense of logic and reasoning screamed for her to apologize and run away, her horny body thrummed with approval as she gave voice to its deepest desires.

“That, young Princess, is the crux of the lesson. I am all yours until you are relieved.” Celestia gazed at Twilight with her soft magenta eyes.

Within them, Twilight found a genuine affection that seemed to extend far beyond the confines of motherly love. The kindness, gentleness, and understanding gave her solace. Her heart banged against her chest as she delved further into Celestia's fathoms deep eyes, and found what she could have sworn was a twinkle of the same raw passion and desire she felt.

Celestia freed Twilight from her bonds, and pulled her close with a foreleg. Twilight rubbed her head against Celestia's neck, then brushed her muzzle against hers. Celestia's wings flared as her tongue darted out and parted Twilight's lips. This time, Twilight's tongue waltzed in harmony with Celestia's.

Twilight's body tingled as her previously out-of-control lust channeled into her lover's tongue, which acted almost as a lightning rod for her passion. Her free forehooves snaked outward and caressed the elder Princess's neck as all else around them seemed frozen by their slow kiss. Her hind legs gripped Celestia's body reflexively as she felt a forehoof venturing forth into her foal garden.

Twilight bucked her hips against the forehoof that probed ever deeper. It did not take long for Celestia to find her g-spot; as soon as the hoof brushed against it, Twilight's body shuddered, and her tongue whipped against Celestia's. Grinning mid-kiss, Celestia mercilessly stimulated the spot, sending mind-shattering euphoric waves crashing against Twilight's body.

In less than a minute, Twilight felt herself drawing close. As another orgasm brewed within her, Celestia's hoof withdrew from her clenching pussy with a loud pop! Twilight broke their kiss and loosed a guttural moan. She was on the razor's edge of orgasm. So much as one more second of Celestia's would have probably pushed her over. She lay on her teacher's stomach, panting heavily.

“Very good, Twilight,” said Celestia, patting her head. “By learning to focus your lust, you have passed lesson two.” She sat up, allowing Twilight to slide off her. She held Twilight close with one of her wings. “Now, my student, we begin the most important lesson of all. It is best done with a partner in the first few cases of wing priapism.”

Celestia's horn shimmered, growing brighter until a thin forcefield enveloped it. Her eyes flicked upward before focusing once again on her younger counterpart. “Think you can take it all?”

Twilight would have recoiled if she was not trapped by Celestia's gentle wing. “It'll skewer me! It's so big and sharp!”

“And hard,” said Celestia, flashing a naughty grin. “I have encased it in a protective shield. I have spent a great many years perfecting this spell; my horn should feel no different, if not better, than a stallion's endowment.”

While Celestia spoke, Twilight's forehoof ventured forth. Drawn by a puddle of fluid that she did not think was her own, she felt the heat of Celestia's marehood upon it. “But what about you?” She tickled Celestia's slick nether lips, and found that her state of arousal rivaled her own.

The tiniest hint of a moan sounded in Celestia's throat. “Oh, yes. It has been building ever since I whisked you away from Ponyville. I cannot hold it back any longer. Do you remember the spell you used prior to my arrival?”

Twilight rubbed harder while pushing her hoof a few inches in. “Yes.”

“Use it.” Celestia bit her lower lip quivering. “Please...”

Twilight frowned. Her hoof stopped moving, though it remained inside Celestia's snatch. “Are you sure? I mean, that it's okay that we do this.”

Celestia inched her hips forward, forcing Twilight's hoof farther in. “Yes. I have felt that there is something special about you for years... Sometimes, it hurt, being left wanting for so long. But I had to wait. Wait until you were ready... and that day has finally come.”

Twilight froze in place, feeling paralyzed by Celestia's words. “I... I don't understand,” she said after a long pause. “I'm hardly experienced in this sort of –”

Celestia silenced her with a kiss on the muzzle. She rubbed necks with Twilight. “But you are ready, my student. You have learned so much about friendship and love. By doing so, you have prepared yourself. This may be a new field for you, but with my... hooves-on instruction, you will no doubt learn everything I know, in time.”

“But –”

“Twilight Sparkle, when I took you in, I saw a wonderful filly with the greatest potential I had ever seen,” Celestia cooed. “You have realized that potential, and grown into an astounding mare. I knew I could not involve myself with you in the way I desired before, for should you have failed, the eventual heartbreak would have torn me asunder.” She blinked back tears as she held Twilight closer. “Now, you have become what I am – that is, eternal. We can be eternal, Twilight. Will you now take my horn?”

Twilight felt tears well in her own eyes. “Yes, yes, I will.” Her trembling lips managed to form a broad smile.

Celestia released her from her embrace, and wiped her lover's tears with her wingtip. “Good. Now, perform your spell.”

After a moment of concentration, Twilight conjured the same shape she had used earlier. It gave a faint hum as it hovered between them.

Celestia frowned. “That size will not do. You must understand that I am a larger mare, and as such, require a significantly larger...” – a shade of pink spread across her cheeks – “... device.”

Twilight giggled. “Oh, right, of course. How silly of me.” Her horn glowed brighter, and the toy grew in size until it reached eighteen inches, and was as wide as Twilight's forehoof.

Celestia shook her head. “I have a feeling that is about your measurements, is it not?”

As Twilight nodded, the dildo thickened and grew another four inches.

“Better,” said Celestia, eyeing it up and down, “but bigger.”

“But, Princess –”

“You may address me as Celestia now, I think.”

“Celestia,” the word felt awkward as she spoke it. “It's already at twenty-two inches. I haven't heard of any stallions that big! Why, even my brother –”

“You have not met the right stallions, then,” said Celestia, with a hungry look in her eyes that Twilight had not seen before. “Bigger.”

The magical toy elongated to an impressive twenty-seven inches long, and significantly thicker than either of their hooves. “I don't know how much bigger I can make this thing while still keeping it stable.”

Celestia held it in her forehooves and gave it an experimental lick. “This will do.”

“I still don't see how you plan on taking that whole thing,” said Twilight, scratching her head.

“Perhaps when you have fully matured as an alicorn, you will understand,” said Celestia as she positioned the toy on the bed. Standing up, it looked more like an imposing magenta monolith than an interhorse toy. Celestia rose to her full, towering height, and slid the head into her marehood. She bit down on her lip, and moaned as the toy penetrated her.

Twilight's mouth fell open as she watched Celestia's pussy devour inch after inch of her toy like Pinkie Pie devoured pastries. Her arousal skyrocketed when Celestia reached the halfway mark. Celestia's bodacious, perfect flank bobbed up and down as she humped it like a horny schoolfilly, taking slightly more with each downward stroke.

It was truly an incredible sight to behold. Too enthralled to maresturbate, Twilight began to drool as Celestia began to consume the final half-dozen inches. Ever since she had started to mature, Twilight always regarded her as beautiful and attractive, but now, Celestia was the pinnacle of pony sexuality. She was perfection. A gust ruffled Twilight's mane as Celestia beat her great wings as she neared the toy's base. In one final thrust, Celestia bottomed out with a whinny that stripped the air from her lungs. Celestia bowed her head and panted huskily.

“Oh, Twilight – oh, Twilight – I – I haven't been so full in centuries!” She pawed at the bed before turning around. “Spank me.”

Twilight blinked. “Excuse me?”

“Just – just do it!” She presented herself to her student.

Twilight gulped before complying. The bedchamber echoed with the sound of her forehoof connecting with Celestia's supple flank.

“Aah! Harder!”

Another spank, this time accompanied by a feminine grunt from Celestia.

“Harder!”

A third spank left a red impression in the centre of her cutie mark. Celestia whinnied again, and snaked her enchanted tail around the back of Twilight's head, pulling her in. As soon as Twilight's muzzle forcibly met Celestia's royal treasure, Celestia came.

Twilight's nostrils flared as Celestia's heavenly scent filled them. Intoxicated, Twilight eagerly lapped up the divine fluid flowing from Celestia's nethers. Her taste buds sang a happy melody in her brain as she drank the nectar. She could not help but grope Celestia's flank as the Princess's eyes rolled madly in the throes of her orgasm.

When Celestia regained enough of her composure, she turned around, and licked Twilight's face clean of her own fluids. “Mmm... are you ready for me now, my student?”

“Oh, Celestia, take me!” Twilight kissed her.

“Turn around.”

Twilight obeyed and prepared herself. She gasped as Celestia's muzzle poked around her hungry fillyhood. A wave of pleasure nearly floored her as Celestia's tongue hit her g-spot without warning; somehow Celestia remembered exactly where it was. Twilight fell face-first on the pillow as the sudden state of near-orgasm grasped her.

Celestia withdrew. “Oh, somepony is ready.”

Twilight could only manage a whimper before Celestia's horn entered her. She bit down on the pillow as the horn slowly and relentlessly drilled deep. The thin magic cushion surrounding it stimulated nerve endings Twilight did not know she possessed. It far surpassed the feeling of any horse cock or dildo – magic or otherwise – she ever had inside her.

The two of them worked together to achieve full penetration; Celestia eased her head forward, while Twilight spread her hind legs, and pushed herself backward, trying to accommodate as much of Celestia's massive horn as possible. What made this a difficult task for Twilight was not only its unprecedented length, but also how much wider it was as she neared the base.

Twilight finally felt her flank press against Celestia's forehead when the horn tip had nearly reached her cervix. Worn from her previous exertions, Twilight rocked her hips as she came, showering Celestia's head with her filly fluid. Instead of coming down, her pleasure only continued to mount.

“Very good,” said Celestia as she slurped at Twilight's love juices. “Now move the stimulant inside. Do not hold back.”

Twilight began to slide it in and out of Celestia's gripping pussy. She moved it slowly at first, and only with about six-inch thrusts, but increased her pace after a few seconds. All the while, she humped against Celestia's horn as hard as she could, all fear of it gone.

The two alicorns cried out in unison as their lovemaking reached fever pitch. Twilight now battered her dildo in her lover as far as it would go with two-foot thrusts. Meanwhile, Celestia stood over her, and plunged her horn into hard, twisting her neck to create a drilling effect. Each climax's conclusion was superseded by a fresh climax.

“Oh, Twilight, you're so incredible! I – I can't hold out much longer!” Celestia's words came strangled as she fought to maintain control.

“N-neither can I,” Twilight whispered.

“I can raise the sun,” said Celestia, her tones hushed and sincere, “but you bring more brightness to my life than it ever has.”

The words drummed against Twilight's frantically beating heart. Using the last of her arcane acumen, Twilight withdrew the dildo until only its head remained within her lover, and then smashed it against her cervix with tremendous force. The resulting shockwave caused Celestia to thrust her horn with just as much force.

It was too much. A crescendo of lust, fulfillment, love, and stimulation shook Twilight to her core. She lost all control, and her spell faded. Her limbs – including her wings – thrashed around in primal ecstasy as she came with everything she had. The sound of Celestia's wail from cloud nine barely registered that she found herself in the same place.

Twilight yearned for her orgasm to never end. She could not compare it to anything she had felt before. Just when she thought her brain would explode from the overload of her tremendous climax, it began to die down. She slid off Celestia's juice-soaked horn and lay flat on her back. Her wings had mercifully folded. Celestia regarded her with a warm smile, a smile comparable to the one she had always worn when Twilight had mastered a complicated spell as a filly.

Twilight stared at her with wide, shining eyes. She raised her forelegs to her chest. “Did – did I pass the lesson?”

Celestia leaned in and kissed her deeply, her tongue preforming a long, slow circle of her mouth before she withdrew. “Yes, I'd say you did, my student. With a perfect score, no less.”

Twilight's eyes fluttered shut. “Good...”

The last thing she felt was the gentle wetness of Celestia kissing her on each cheek, and then her soft, nurturing wing, closing in around her as Celestia tucked her in for a good, long slumber.