Fluttershy realized she was quickly finding every reason to be worried. These clothes couldn't possibly look good on her, she had no idea what kind of lunch was awaiting them, they were in Canterlot's palace for Celestia's sake, and she was coming, to eat with them, to talk with them, and she still didn't have any idea what Rarity had planned. So she stood, nervously, in the short hallway near the Observatory, and tried not to be too large of a presence in the way- Colts and mares were passing all the time, although the door in front of them had yet to open. Thankfully, nopony was getting too close or bothering them, so she could just sorta hover at this level of slightly frazzled nerves. Maybe she could even calm down, if she got the chance! ...Yeah, that was probably asking for a bit much.

She was almost going to turn around when she felt the presence behind her, and the shadow cast across her, but before she even got the chance, it was too late. Ambushed, taken by surprise, she squeaked as all the air was knocked out of her by an impressively fierce hug. She couldn't feel anything but warm and soft and there were stars everywhere... Oh. And the voice. This was...

"OH DEAR FLUTTERSHY! WE HAD BEEN HOPING TO THANK THOU FOR... YOUR... Ahem. As We were saying, We had been hoping to thank thou for thine lessons! We had no idea that it was thou with whom We had this meeting."
Princess Luna let go of her, and she took in a deep, shuddering breath (and tried to keep her wings under control at the scent of midnight flowers in Luna's mane) to try and calm down. She shrunk back, smiling, and accepted the thanks- or tried, but her voice was completely escaping her. Luckily, her friends were there to back her up.

"Ah, Princess Luna, it's an honor to meet you again- I do apologize for not being there to greet you on Nightmare Night, but I was somewhat occupied."
Rarity stepped forward and bowed, diverting Luna's attention from her own awkward silence.

"Oh, thou art quite the courteous member of court- Rarity, yes? One of those who brought me low upon my return?"
And at this, Rarity got a bit of a nervous look, desperately looking to her and Twilight for help, but then Luna laughed. Fluttershy hadn't heard that before, her laughing, at least not since she was the Nightmare, and... she really wanted to hear it again.

"I kid, I kid. Or I try. It has been a slow adaptation, We must admit. I still find myself taking the Royal voice from time to time... A hard habit to break."

Someone responded to her with a little chuckle.
"Oh, that's perfectly fine Princess. I really like your regal tone."

She was trying to figure out who had said that until she realized it was her and brought a hoof to her mouth in shock. Why did she just say that? Oh this was going to be terrible Luna would get angry and then everything would--

But her fretting was interrupted by that laugh, clear and bright in the air, as Luna gently placed a hoof on her shoulder. "Thank thee very much, dear Fluttershy. We are glad that even our flaws are appreciated amongst our subjects." She squeaked out some indecipherable reply and then Luna opened the door to the outside of the tower, revealing a beautiful balcony table that overlooked the entire valley below.
"Shall we sit down for a meal and discuss what brought you all here?"

--------

A short visit from the waiter to ask about drinks later, they were all (except for Fluttershy, who still seemed a bit... frazzled) relaxing on the small veranda, Rarity and Luna dominating the conversation-- Which was perfectly reasonable. After all, they had yet to meet, and Rarity was the one with the most experience in matters of royal etiquette, so she knew just what to say, what to ask, and when to listen. So as Rarity and Luna talked, Twilight did her best to make Fluttershy a bit calmer.
"It's alright-- I think you did fine out there!"

The reply took its time in coming.
"Do you... think so?"

"Yeah! She seemed to really like the compliment, and she did give you a hug as a greeting- So at the very least she thinks of you as a friendly pony."

"Oh, that is true. I guess I really was just worrying too much."
Before they could actually talk about anything else, however, the drinks arrived, Rarity had to pause, and Princess Luna asked the question Twilight had been dreading.

"So, what did bring everypony up here to meet with me, and on such short notice?"

Fluttershy looked desperately to Twilight.
She looked desperately to Rarity.
Rarity just smiled-- She was in her element today, after all.
"Oh, I had just been spending some time with my friends, hearing about their meeting with you on, ah, your Night, and in part I admit I had selfishly wanted to meet you myself."

The Princess smiled and waved a hoof dismissively.
"We had actually wished to meet thou as well, to complete the set, as it were, and speak to all those responsible for helping us."

"I did have another motivation, actually, but I had been a bit hesitant to bring it up."

"Speak freely, Rarity of Ponyville- You have asked for, and received, audience, you need not fear our reaction."

"Well... You have been gone from Equestria for ever such a long time, and things have changed, and I had the most dreadful thought- You probably do not have a substantial wardrobe any longer, do you?"

"Ah. We... no. That is very true. Our dear sister kept out affairs and maintained so many of our things, but... cloth is just so perishable."

"Yes, well, fashion is also quite perishable, even if it does move in cycles- And I had been thinking, perhaps you would be interested in my services? To replace what you had, and update what you lost?"

Princess Luna paused, as their food arrived, a spread of various foods, a hot soup and delicate sandwiches, lovely small salads and fresh drinks for each of them. The waiter was utterly unobtrusive, leaving just as quickly as he entered.
"We... I, I think I would like that. I do admit that I was never terribly in tune with modern fashion before I left, and what little skill I had is long gone."

"It is totally understandable, Princess. And while Canterlot may have significant resources, I find it often helps to have the personal touch of a friend working on things."

Luna was silent then. Twilight wasn't quite sure what that expression was, but eventually it gave way to to a tentative smile.
"Art thou saying... Are you saying you want to be friends? Our friends?"

"Well of course! What's in the past is behind us, and you are someone we would love to get to know. Isn't that right, girls?"

"Absolutely!"

Fluttershy's response was a surprisingly loud and excited "Of course!", after which the Princess laughed, sending them all into a little burst of the giggles.

"Thank you. Thank all of you. I think that would be lovely."
Rarity smiled widely and put a hoof across the table for a gentle shake.

"I am glad to hear it! And, if you have a moment, I did have another question... After we eat, of course!"

--------

After the meal was finished, Fluttershy was grinning widely, a slightly dazed look in her eyes and a sort of subtle twinging to her wings. Rarity was pleased, absolutely ecstatic herself-- She had pulled off everything without a single hitch, and if word got around that she was doing business in royal circles... Oh, this was just perfect! And the two of them were heading back to Ponyville ahead of Twilight, since the little favor they asked for from Luna could be acted out without them.

"Rarity, are you sure Twilight will be alright without you?"

"Don't you mean without us?"

"Uhm, no. I'm not sure how much help I would really be."

She sighed and put on hoof on the other mare's shoulder. "Fluttershy, I am absolutely certain that you would be able to support Twilight, but yes, I do believe she'll be fine."

And so they went out, returned their borrowed dresses to The Crop, and headed back to Ponyville. They would greet Twilight on her return later that night, and find out how everything went.

--------

"And? How did everything go!?"
Rarity was a bit over-excited, and Twilight couldn't exactly blame her- They'd left early, and Twilight was just barely getting back to Ponyville in the middle of the night, looking a bit sleepy-eyed.

"Things were very nice. Celestia was a bit surprised to see me, it turns out, but in the end, she was proud of the initiative I took, and she said yes!"
Fluttershy let out a slightly-louder-than-normal cheer, Rarity clapped, and she felt like jumping around doing her Yes Dance, but... Now was not the time, everypony was asleep.

They quickly finished discussing the new developments, set aside some time in their schedules for the inevitable party when Pinkie was informed, and then headed off to their respective homes-- There was a rain shower scheduled in an hour or two, and nopony wanted to be there if it ended up early.

When she made it to the library, the first thing she noticed was the light in the windows. Oh shoot, Spike was home from his business. And waiting up. Which means he was probably worried, which means she was going to get an earful the moment she opened the--

"Twilight Sparkle! And I thought you were supposed to be the one responsible for me!"
Yup. As soon as she opened the door.

"Oh Spike, just let me inside and I can explain. I was on royal business."

That got him to step back in surprise, and do a little fake bow as he ushered her into the room. She stepped inside, and then she kicked the door shut gently, shaking her head from side to side and relaxing her neck- She'd been out and about for quite a while longer than usual.
"Well then, what did keep you up so late?"

"Me, Rarity and Fluttershy had a meeting with Princess Luna, and then I had a private meeting with Princess Celestia."

"R-rarity? Aaw man, that's why she was gone all day! What were you all doing there?"

"We, ah, had a bit of an arrangement to suggest with the Princesses, and it worked out perfectly."

"What was it?"

"You'll see. I'm sure everypony's going to hear about it once Pinkie finds out." She giggled and walked upstairs, leaving her confused little helper to close down for the night-- She had a book to find.

--------

Finally, on a relatively dusty (which is to say, had not been dusted that day) shelf, she found the book she had been looking for. Or, at least, a book, that might be what she was looking for. She hadn't ever heard of it before, but, well... she hadn't really had much time to study relationships and things like that, now had she? It was totally understandable that she was a bit inexperienced in the subject matter, despite her age, because first she was studying magic, and then friendship, and frankly she had been very busy for quite some time. But hopefully this book would be able to help her on that matter-- I mean, just look at it! A very solid black-cloth bound book, subtle, unassuming, with the title printed up the spine in gold ink:

The KaMare Sutra, or The Ways Of Pony Love: Forty-Six Ways For Mares To Come Together.

It was really a nice title, and would obviously show her a variety of methods for asking somepony out on a date, or how to start a relationship, as opposed to anything else.

--------
TIME PASSES...
--------

It was about an hour later, and she had not moved an inch from the spot, still reading, slowly turning pages, her mouth slightly open, her breathing a bit heavy, and that same rushed heat between her legs was back. The book had started out pretty normally, but then she got into the second chapter. And the illustrations. They were... quite detailed, actually, and showed her things she had never thought of before, but now she couldn't really think of anything else. Mares in various positions, standing, sitting, lying-down, doing... things with each other, and even in the artistically-minimalist images, it was clear how much they were enjoying themselves. The accompanying text captions, summarizing the 'action', as it were, got her mind racing, and at this point she was actively rubbing her legs together, gasping a little here and there.

She wasn't entirely sure how to deal with this, but she realized how nice the rubbing sensation was, and the illustrations suggested... a certain solution, which she was envisioning. So she made sure everything was locked down, made her way (shakily) upstairs, and then set the book to levitate above her bed and turn its own pages every once in a while. She rested beneath it, looked up, and adjusted a few pillows. Doing new things always meant you could afford to be methodical, even if that sensation she was feeling made her want to hurry hurry hurry.

She took a calming breath, made sure the door was locked and Spike was sleeping elsewhere, and then spread her legs and looked down at herself. She didn't really pay attention to her own body, especially that bit, when she wasn't actually taking a bath or grooming. Right now, though, the difference from usual was... apparent. Gingerly, she brought a hoof down and made contact with herself, and the shock that ran up her back made her apply more pressure, already gasping a bit. It took a minute or two, but eventually she managed to tear her attention away from herself and look up to the book.

It had progressed into a new chapter, color illustrations... no wait. Pictures, actual photographs, of mares in bed with each other, acting out the rest of the book's illustrations in full color. They were all beautiful, seemed to be excited and happy, and the difference in looking at them was shocking. She kept pushing down on herself, rubbing back and forth, building up a bit of friction, until the book swung open to a new page and she nearly stopped in shock. She ordered it to stop turning, and looked closer. It wasn't her, but... The white coat and horn, a long flowing mane dyed in stripes. It was very clear who it was supposed to be, and the fire inside her just flared to a peak at that.

She'd barely been looking at the picture for any time at all, subconsciously drawing the book closer, when she finally hit a little spot that caused her to thrust her hips up into her own hoof and groan, trying to pretend it was a random sound and not a name she just said. But soon even that illusion was pointless, as she kept coming back to that spot, the picture mere inches from her face, and Celestia's revered name on her lips.

Her climax was loud, messy, and absolutely staggering- She had never felt this way before, and it was simultaneously the most invigorating and exhausting thing. She levitated the book down, set it on the night stand, pulled up the covers, and resolved to clean the sheets in the morning- For now, she was content to sleep on this phenomenal feeling.

She could not wait to tell the girls what she'd figured out.