Canterlot Lessons

by RandomString

Rating: teen
Tags: Sex, Princess Celestia, Twilight Sparkle, Princess Luna, My Little Pony: Friendship is Magic, Romance
Length: 4602

Luna notices the mutual interest between Twilight, her lover, and Celestia, her sister. What would loving sister to do?

Edited / proof-read by Knight of Cerebus

Princess Luna hatches a cunning plan when she notices an attraction between her lover, Twilight Sparkle, and Celestia.

Twilunestia, no incest.
This story skirts the edges of what's permissible for the Teen tag. If that sounds bad to you, please don't read this story.

Published 2014-07-06 12:40:03 UTC
Last updated 2014-07-06 12:40:03 UTC

Canterlot Lessons

Twilight was a connoisseur of reading spaces. She had a nose for finding those hidden nooks and crannies where a pony could relax in lazy comfort and get some solid reading done. She had a study in her castle, of course, but that was cheating. Reading there had none of the comfort of hiding in the snug, surreptitious safety of someplace where nopony would think to look for her.

She rated her current reading place rather poorly, despite being excellent by many of her usual metrics. It was comfortable, with a huge beanbag and a multitude of soft, warm blankets. As the equal-highest balcony of Canterlot Castle, it had a spectacular view of the city below. There was even a telescope that she grudgingly had to admit was better than hers. It had several bookcases overladen with ancient tomes within easy reach. By almost any standard it was perfect. There was only one problem: it was owned by a bored, imaginative, sexy, and affectionate Princess of the Night who refused to let her read.

At present, Her Serene Highness, Princess Twilight Sparkle was trying to ignore Her Royal Highness, Princess Luna, who was nibbling on her ear. After several months of flying visits and stolen weekends, Twilight's willpower and ability to resist her lover's entreaties was phenomenal. After fifteen minutes, Princess Luna could tell that she wasn’t getting anywhere, and tried a different approach.

"So, what are you reading that is so much more interesting than me?"

"The letters I wrote to you," said Twilight, "and they're not more interesting. It's just that we eat in half an hour or so, and if I give in to you now then we're going to turn up late, hot and sweaty. Again."

"But I like arriving late, hot and sweaty. Particularly if it's your sweat. Mmmm..."

Twilight swatted Luna's flank with her tail, but made no other response, completely focussed on the scroll in front of her.

Luna humphed in disappointment, and tried again.

"So how did you find those letters? I thought I had them safely locked away."

"You did, but I was bored. And with Rarity refusing my help in preparing for her birthday party tomorrow, I needed something to do."

"While I am very grateful for your friends’ dedication to giving us excuses to be together, they could think to check my schedule during their plotting. Even so, couldn't my little library keep you occupied?" asked Luna, waving a hoof at her set of bookshelves. Bookshelves that she noticed now looked suspiciously well organised.

"I've read everything in there."

"Everything? Three thousand years of lore absorbed just like that?"

"Well, there are copies of a lot of those books in the Canterlot library, you know. And night court takes ages, you see."

"So, having exhausted my poor library, you found the spell-locked chest hidden inside the mirror in my boudoir, defeated its guardian, cracked the lock and dispelled the protective enchantments just to read some scrolls that you wrote?!"

"Luna, I don't think you appreciate quite how long you were gone for. It was hours. Anyway, these scrolls are really funny."

"Funny? Twilight, the first scroll consists of three pages of you ranting at me for 'destroying the work of fifty generations of astronomers' when I re-arranged the night sky to a more pleasing configuration."

"I know! It's hilarious! To be fair, your response was just as angry."

"I was maybe feeling a little defensive."

"A little?! You threatened to turn me into a basalt statue and banish me to Tartarus."

"So, of course, you sent me a five page response explaining why that would be impossible."

"Five scientifically correct pages. Basalt is an igneous rock, you know. You can’t convert organic matter into igneous rocks; it just crumbles under the forces involved."

"Hmph. I still say that it could be done. Still, do you remember when it all came to a head and you stormed into my study to finally have it out? One moment we were standing snout to snout, horns blazing, and then you kissed me. I didn't realise that you felt that way."

"You just looked so cute, trying to use Dr. Tenebrous' Terrible Transmogrification on me. I just couldn't help myself."

Both mares sighed in happy reminiscence, oblivious to the trauma their fight had caused the palace guard. And the palace architecture.

Luna hugged Twilight, who turned her head to nuzzle Luna affectionately. Luna leaned in. They kissed, and the scrolls rolled away from the love nest, forgotten. They were going to be late for supper. Again.

Twilight and Celestia were reminiscing over Twilight's student days. Princess Luna quietly sipped her coffee and listened with warm amusement. She loved her sister, but it was always nice to have somepony else at the table for pleasant conversation. Indeed, the food had now long been consumed, and yet they stayed at the table, loathe to leave each other’s company.

"–Ha ha! I must have been an awful student to start with, huh? If a subject didn't have anything to do with magic, I just wasn't interested."

"Twilight, you do yourself an injustice. I admit that your unique focus was a bit off putting for your other tutors, but you were always completely attentive whenever you were with me."

"Well, of course..."

Celestia's smile was serene.

"It was quite adorable, really. Shall I tell you a secret?"

Twilight leaned forward with an eager smile.

"I conspired with your teachers. I would give you an introduction to a subject and ask you to study it further. You would then immediately gallop to your other tutors and demand that they teach you everything about the topic. It worked quite well, really."

Twilight's blush brought a more knowing smile to Celestia's face, and a giggle to Luna's lips. Twilight hid her head under her hooves.

"Of course, it didn’t take long for your studious nature to kick in. Soon you were trying to preempt all my suggested topics, and then you started grilling your tutors for information that was most definitely not on the syllabus."

"Oh! I remember that! Poor Professor Stone. She was leading a seminar on erisian-era sugar glaciation when I burst into the room and demanded she teach me everything there is to know about soil erosion. I really need to apologise to her again."

"She forgave you long ago," replied Celestia, "She told me she just wished that her other students were that motivated. Everypony loved your dedication to learning. Even Doctor Heart forgave you when you–"

"Ah! Don’t remind me!"

"What’s this?" asked Luna, her interest caught by Twilight’s sudden blush.

Twilight hung her head in her hooves. Celestia grinned as she told the story.

"When she was seven, Twilight found the long term curriculum I had drawn up for her. She understood the headings for most of the topics, but one line far down on the list really stumped her."

"You had told me off for trying to learn everything from books," Twilight said to the table, "so I didn’t use a dictionary for the words I didn’t understand. Instead, I went to a pony who was in the listed department."

Celestia grinned broadly at Luna’s expression.

"Twilight ran into Doctor Strong Heart’s study, where he was discussing the possibility of tenure with the Dean of Canterlot College, and asked for him to teach her everything about sex."

Twilight buried her head deeper at the sisters’ good-natured laughter.

"That was when I realised that learning from books was much, much better than learning from ponies."

"Twilight!" exclaimed Luna, "I thought you enjoyed our little lessons. I’m heart-broken that you were only humouring me."

Twilight cast frantic glances between Luna and Celestia, her blush growing to the point of incandescence.

"Um," she said, "Um. I may have been a little hasty– Wait a moment! You’re playing with me!"

"Sorry, Twilight," said Luna, "You’re just too adorable."

"Hmph. Well, if you want to teach me anything more on the topic, you’re first going to have to show me just how adorable I am. Repeatedly."

With a playful grin, Twilight rose from the table and headed for the exit. She held her nose in the air in mock defiance, and tried to put a offended wiggle in her walk as she left.

Luna noticed her sister's wistful sigh at the sight, and then noticed that her lover was almost at the door without her. She hurriedly made her excuses and joined Twilight.

Rarity had wept tears of joy when Pinkie Pie had explained the plan for the fashionista's birthday party. Pinkie Pie had gotten permission to hold the event in the palace. This meant, of course, that no fewer than three Princesses would be in attendance, making it a keystone social event of the season. The jockeying amongst the movers and shakers of Canterlot to get onto the guest list, which had been under Rarity's control, had been absolutely wonderful.

The hectic days of preparations and receptions and invitations would have been overwhelming for Rarity without the help of her friends. Or, at least, most of them. Rarity had, of course, banished Twilight to Luna’s chambers from the moment the party of party-throwers had arrived in Canterlot. In Rarity’s mind, romance always came first.

The party had gone swimmingly. Rarity had made the gowns the Princesses wore to the party, which had been sparkling off-the-shoulder affairs that reflected the light from the candelabras to make it appear as though they were clothed in stars. Once Princess Celestia had casually let drop who the designer was, Rarity had been inundated with accolades and business enquiries. She couldn't have been happier.

After a few drinks, and as much sycophantic socialising as they could take, Princesses Celestia and Luna had retired, leaving Rarity to shine as the centre of attention and allowing the partygoers to relax and let their manes down a little.

Nopony noticed Princess Luna swipe a couple of large bottles of champagne on the way out. Princess Celestia grabbed the glasses. And some cake.

Luna laughed as she chased the giggling Celestia towards her sister's quarters. Breezing past the guardponies, they collapsed onto the great bed.

Opposite Princess Celestia's bed was a wall-mounted, gilt-edged, full-length mirror. Those few servants who were privileged enough to enter her quarters often wondered at its placement. Very few of them realised that it was a scrying mirror.

Celestia tuned the mirror to show the party that they had just left. Luna poured the wine, and offered her sister a glass once the mirror was set. Celestia accepted the glass with a smile and settled next to her on the bed.

If there was one thing Celestia had missed most about her sister, it was somepony that she could gossip with freely. This would be a great evening.

"Ha ha! Look at Twilight dance! You taught her all that magic and yet you never had somepony teach her how to dance properly?"

"I never had the heart. Can you see how much fun she's having? How enthusiastic she is? Having Twilight in the palace as she grew up was such a breath of fresh air," Celestia sighed happily as her student nearly sent a plate of canapés flying when its bearer got a little too close, "You see her more than I do, nowadays anyway. You teach her."

"No thank you, 'Tia. I am still having too much fun teaching her other arts," Luna grinned at her sister and waggled her eyebrows suggestively.

Princess Celestia hit her sister with a pillow.

"Oof. You are just jealous that I bedded her first."

Princess Celestia hit Princess Luna with a pillow again. Harder.

The party was soon forgotten. The pillow fight quickly degenerated into a tickle fight after the sisters found that horns and pillows don’t mix. The ticklefight in turn morphed into a flying game of tag amongst the spires of Canterlot. The sisters swooped and dove around the towers, shrieking joyful insults at each other between great lungfuls of air. The partygoers took to the verandas and fondly watched the sisters play into the night.

Princess Luna had a large mirror in her bedroom, too. It wasn't enchanted, it was just there so that she could watch Twilight's face no matter what position they were in.

A dazed Twilight stared into it. Her eyes were not really taking anything in, and she was too exhausted to turn her head. When Luna kissed Twilight at just the right place on the nape of her neck, Twilight rolled away a little with a groan, giving enough room for Luna to lie down beside her.

"Where..."

"Hmm. What was that, love?"

"Where do you get the energy from? Is there a fusion core in the moon that you can tap into or something?"

"I take it that you enjoyed my efforts?"

"Mmmmmm"

"Good," another kiss sent a tingle down Twilight's spine, "and no, our endurance is just a part of our heritage. You are a newly fledged alicorn, your stamina will increase as you grow," Twilight could see Luna's grin in the mirror, "I am very much looking forward to it."

Twilight groaned, even as she felt strength return to her limbs. She righted herself and settled into a more comfortable position.

"See? You are lasting a lot longer already. My poor toys will probably not last another month if your friends keep making excuses for you to visit Canterlot. You will note that I am not complaining, mind you."

"Their noble sacrifice is well appreciated, and I’m sure that Rainbow Dash’s suggestion that she and I attend the Wonderbolt show here in a couple of weeks, in the Royal Enclosure, no less, is entirely selfless," Twilight sighed, "I just don't feel any stronger than I was before."

"Oh, do not worry, you are. You could easily keep up with an earth pony mare now, and that will only improve."

Twilight idly grabbed a goblet of water and drank thirstily.

"On the other hoof, a physically active earth pony stallion," continued Luna, "well, let us say that you still have a way to go. I remember Unfailing Bulwark. The captain of 'Tia's guard, some time back before my exile. A real stallion. Handsome too. He could rut her to exhaustion every time."

Real princesses don't spit-take, Twilight reminded herself, too late.

Luna continued heedlessly, "We had to team up, taking turns, before he was spent. That was fun." Luna smiled, looking off into the distance. Twilight choked for air.

"–What?! Wait– You and Princess– You teamed up?!"

"Why so shocked? We lived and ruled together for centuries, with only each other as constants. We got very close. Anyway, we both like the same things in our lovers, and we are both very picky. Good ones are so rare that sharing them only makes sense. You do not want me to fight with my sister, do you?"

"No, no. It's just. Um. Surprising. Eye opening. Revelatory. Um. Wow."

"Oooh. Are you interested in being shared, Twilight?"

"What? No! I couldn't. I mean we couldn't. I mean, it's Princess Celestia! We can't– I shouldn't– I mean–"

Twilight was silenced by a kiss.

"Do not fret, Twilight. I did not intend to upset you– Oh, I have a fun idea. How about we play a game?"

"A game?"

"Yes. How about we give poor Mr. Strap-On a break for one night. I shall invite you up to your old quarters in the library observatory and disguise myself as 'Tia. Have you ever had fantasies of seducing my sister, Twilight? Before you met me, of course?"

"Well, of course– I mean it's Princess Celestia! Who hasn't– I mean, No! Of course not! The–"

Another kiss.

"So it is agreed. I shall play poor, innocent 'Tia, who has agreed to teach her favourite student one more lesson for old time's sake. You shall play the flirtatious student who tries to seduce her teacher until the lesson dissolves into lusty, passionate sex! Does that sound fun to you?"

Luna suddenly noticed that Twilight's eyes were pinpricks, her body was rigid and a trail of drool was coming from the corner of her mouth. Luna smirked.

"Twilight?"

"Uh? What? I was–"

"Twilight, do you want to play as 'Naughty Student' to my 'Great Teacher Celestia'?"

"Uh. Yes. Yes. I would like that. Yes."

"Good. Now, you appear to be rested again, so shall we see if our recent exercise has improved your endurance at all?"

My Faithful Twilight,

Your presence back at the palace has brought so many fond memories of the bond we shared as student and mentor. If you would like to reminisce and humour an old mare, I would love to give you another lesson. Please be in the Library Observatory, an hour after sun fall.

With Love,

Celestia

Spike had confirmed via dragonmail that the library was fine, and Twilight didn't need to hurry back after the party. Twilight's Ponyville friends assured her that she could stay behind for another night in Canterlot; they even kept the innuendo-laden jokes to an absolute minimum. The letter in her hooves was clearly written by Princess Luna.

However she looked at it, Twilight was unable to escape the inevitable conclusion. This was going to happen.

Twilight climbed the spiralling staircase to the observatory at the appointed hour. She hesitantly knocked on the door.

"Come in, Twilight," came the calm and serene voice of her mentor. Twilight peered around the door.

"Princess Celestia?" she called out.

"Twilight, you really should call me Celestia, you know. You are a princess too, now," the voice came from the mezzanine floor, the level above the entrance.

"Sorry, Princess."

The observatory was much as she had left it years ago, but Celestia was standing next to a comfortable nest of blankets, cushions, pillows and bean bags that had been made on the floor. A bottle of poniot grigio was resting in a wine bucket, alongside a couple of fine crystal glasses illuminated by a hovering light globe. She looked very relaxed without her official regalia. She was holding up a copy of Neighton's Principia with a shy smile.

Twilight stood speechless for a moment, and then started to the stairs, hips swaying unconsciously.

"Ooh, the Principia! Do you want to read it with me? I've always been very interested in the movement of bodies."

"If you like, Twilight," said Celestia. The faintest hints of a blush blossomed on her cheeks when she saw the swing in Twilight's gait.

Twilight approached her princess, suppressing an excited giggle. She was tempted to just give in and ravage Luna then and there, but it would be far more fun for both of them if she stretched things out slowly...

Twilight nuzzled the princess in greeting and then settled down in the comfy nest that had been prepared. Celestia settled down a hoof-span away from her and set the book in front of them. Twilight shifted a little until their wings were touching, just.

"I love the Principia," said Twilight, "It's amazing how Neighton established the laws of motion from so few clues. And, of course, the observations and calculations he made concerning your lifting of the sun! Such a poetic paean to your powers. Aheh."

Twilight was finding flirting to be harder than she thought.

Princess Celestia turned to the dedication and smiled absently. Neighton really had been very flattering, and the portrait of her on the frontispiece was a good one. Twilight had suggested a lovely book for them to review in her letter.

Twilight's attempts at seduction were not going well. She kept getting distracted by Neighton's brilliance. She did try a witticism comparing Princess Celestia with a heavenly body, but she managed to sabotage the attempt by clarifying that she didn't think that the Princess was fat. She then went on to explain that she didn’t think that she weighed the equivalent of a solar or even a planetary mass. Her stumbling words then degenerated into a mess of poorly phrased excuses. Princess Celestia calmed Twilight with her name and a serene smile. Twilight could have sworn that she could detect laughter at the edge of her hearing.

Thankfully, there was no sign that the Princess had seen her failed attempts for what they were, and seemed content to work through the book. With a quiet sigh, Twilight forced down her rising desire. There was no denying the obvious conclusion: Luna was playing hard to get.

Luna had never come across to Twilight as the most studious of ponies, and yet here she was, breezing through the Prinicpia, comparing the merits of Neighton's equations with those of the relativity model, and hinting at possible deeper links between gravity and magic. Twilight was even having to struggle to keep up on occasion.

Unfortunately for the bean bag that propped up Twilight’s hindquarters, it was sexy beyond words.

They had finished book one of the Principia when Twilight decided to try and shift the tone. It was clear that despite the rosy tint on Princess Celestia's cheeks, possibly brought about by the wine, discussing celestial mechanics was having more of an effect on Twilight than on her target.

Twilight toyed with the idea of saying 'buck it' and just pouncing on the princess. There was a lot of charm in the thought of just giving in and having her way with her, but this seduction had become a challenge, and Princess Twilight Sparkle didn't back down from challenges.

"Thanks for that, Princess. You've really opened my eyes to new ideas in this old book. That being said, do you mind if we skip book two? It really hasn't held up as well to the test of time."

"Of course, Twilight. And thank you for your comments; I've had a hard time keeping up with modern theoretical physics, and it's always nice to have a refresher. Would you like to start on book three, or would you prefer to find something else for us to read?"

"Let me browse the shelves and see if I can find something good."

Twilight turned to the stacks and desperately started looking for more promising seduction material. 'The Karmare Sutra' was quickly dismissed as being too, ahem, subtle. 'Pony's Anatomy’ was too clinical. Twilight had no idea what a copy of 'Fifty Shades of Hay' was doing in her library, but she discreetly incinerated it before moving on. She was starting to get worried about the time she was taking when a book fell out of the shelves behind her.

'A Pony's Guide to Preening'? That will do, Twilight said to herself. She scooped the book up, but held back from thanking ‘Celestia' for the suggestion – it would ruin the illusion.

"Hold still, Princess. How can I get this right if you keep moving?"

"S– Sorry, Twilight. You seem to keep touching some, ah, sensitive, areas."

Twilight grinned. This was going much better. Under the guise of practicing a standard wing relaxation technique, Twilight was attempting a tantric massage. She and Luna had done similar things before, so she already had a pretty good idea on where the princess was the most sensitive and just how much force to use. The only real difficulty lay in allowing for the larger body Luna was now using.

Twilight knew that she was getting better when 'Celestia' made a noise that was something between a groan and a moan. She found the sound coming from her mentor deeply arousing.

The dark night outside had turned the great observatory windows into a mirror. Twilight could see 'Celestia's' face lit up by the hovering orb of light. Her tongue was lolling out of her mouth, her face was flush, and her eyes had lost their focus.

Technically, 'Celestia' wasn't seduced yet, but Twilight was having a hard time holding back. Another half-hour would be all that it would take. The multi-coloured mane that had featured in so many of her fantasies was drifting a mere hoof-width from her nose.

Twilight leaned in and breathed deep of the scent of summer days, fresh grass and clover. Twilight made a soft groan of her own.

What was left of Twilight's restraint failed, and she licked 'Celestia's' horn from base to tip, eliciting a very surprised yelp and a fountain of golden sparks.

The squirming body that had been beneath Twilight suddenly disappeared, and she dropped onto the cushions. A wide-eyed and focussed Princess Celestia reappeared in front of Twilight, lost for words.

Time seemed to stop for Twilight as she realised what had happened. She lay there for an eternity, staring up at her Princess, trying to think of something to say.

"Tw– Twilight?"

"Princess..."

"Twilight?"

"Princess, I'm so sorry! I didn't mean it! I didn’t know–"

"Twilight."

"–I mean I thought, that is, but I didn't–"

"Twilight."

"–I thought you were Princess Luna! I wouldn't kiss you! Really! No! I mean–"

"Twilight!"

Twilight scrunched her eyes closed, trying to hold back tears. She lay there, trembling, awaiting judgement.

Celestia kissed Twilight with passion, but soon pulled back to see Twilight’s eyes still wide in shock. A look of disappointment fell across Celestia’s face, which was enough to break Twilight from her daze.

"Princess!"

"Twilight," said Celestia, "I am not your princess any more. I am not your tutor. I am not, nor have I ever been, your mother. For all the things that I am not, there is one thing that I would very much like to be: your friend."

"F– friend?"

Celestia shyly smiled, "If you like..."

Twilight immediately perked up, "Oh, yes! I'd love to be your friend! Wait– You are my friend already. We talk, we chat, we exchange letters..."

Celestia let out a fondly exasperated sigh, "I see I wasn't clear enough."

Twilight blinked, but didn't have time to respond before Celestia kissed her again. The princess of the sun was blushing when she finally pulled away again.

"Oh! Oh!. That kind of friend. Um. Um. You see, Princess Luna and I–"

"Twilight," said Celestia warmly, "I take it that my sister lured you here under false pretences, just as she did me?"

"I'm afraid so," said Twilight, "I thought you were her."

"And I thought that you had invited me here for a perfectly chaste evening of scholastic discourse," Celestia laughed, "But considering my sister's scheming, I believe that we can conclude that she has no objection to... sharing?"

"Oh!"

Celestia kissed Twilight again. Her blush faded and her confidence grew with Twilight’s enthusiastic response. They both fell onto the pile of soft bedding.

A sudden thought caused Twilight to pull back. Celestia looked at her curiously.

"I just realised. Luna's watching us right now, isn't she, Princess?"

Princess Celestia sighed.

"She's probably in my room, using my mirror, the minx. Oh well, let's show her what she's missing, shall we?"

Twilight nodded enthusiastically and reached for Celestia, "Yes, Princess!"

"Oh, and Twilight?"

"Yes, Princess?"

"Please call me Celestia."

EPILOGUE

...

"Huh! Huh!”

"Ah! Ah! Aah!"

"Huh! Huh!"

"CELESTIAA!"

"Twilight!"

"Oops! Sorry, Luna."

"Grrr"

*bonk*

"Ow!"

Author's Note

Thanks for reading this far. The story was written as a 'thank you' to Knight of Cerebus for his help with Twilight's Plan.

Please note that if you liked this, my other story, Twilight's Plan, doesn't so much skirt the edges of the 'Mature' tag as leaps gleefully over it and keeps on going.