She found herself continually staring at the sign: "Carousel Boutique". Though she had yet to meet her, she was almost positive this was the home of a unicorn named Rarity, sometimes mentioned in the friendship reports her sister received. She wasn't exactly supposed to see them - they weren't addressed to her, after all - but she still took peeks when Celestia was away. On any given night, Luna would have expected the shop to be shut up tight, and all the lights off. Yet, inside, she could clearly see the silouhette of a unicorn hurrying about to and fro. Given her reputation, it wasn't unlikely that Rarity was hustling to finish an order. She briefly considered the situation, and instantly came up with a fool-proof plan: she would help Rarity finish her order, and earn her friendship in the process! Pleased with how smart she was, Luna approached the door and gently knocked - the silouhette inside took immediate notice and hurried over to the door, quickly opening it. The Princess put on her best smile and was about to speak when she was interrupted.
"I'm terribly sorry, but whatever business you have here will simply have to wait. I'm behind on an order for several clients in Canterlot, and it must be finished by morning. Good night."
With that, Rarity slammed the door shut in Luna's face and hurried back to her work. The Princess knocked once more, and the unicorn within stomped over again, flinging the door open. "For the last time, the shop is closed! Whatever it is you need to do, you'll have to wait until-"
"Miss Rarity, I presume. I'm Princess Luna. Is there any way I could-"
Rarity opened her eyes, all the color draining from the unicorn's face as she quickly realized just who she had slammed the door on earlier. "P-P-P-PRINCESS?! Oh... oh goodness. I'm terribly sorry, Princess! I... I didn't realize! Please, please! Come in, make yourself at home!"
Despite her best efforts to appear professional, it was painfully evident how nervous she was. Luna found it almost comical, but remained silent on the matter. "Royalty! In my shop! My home! P-princess, would you like some tea? Food? Snacks? Anything you desire?"
The Princess laughed, waving a hoof dismissively. "I appreciate the offer, Miss Rarity, but I simply wanted to know if you needed-"
"This won't take long at all! I just need to find some gems and fabrics that match your coat and mane! Oh you'll look positively wonderful, my dear!"
"Miss Rarity, please-"
"No no, I insist! Now this will take just a moment! Let's see... no, too dark. Ugh, that's too bright."
"Rarity-"
"Just imagine the stories I'll be able to tell my foals and fillies, and their foals and fillies! Royalty, in my shop!"
Luna quickly found herself stuck in a corsette, tears welling in her eyes as Rarity continued to pull on the strings, regardless of how tight it already was. She soon found she had no choice but to use 'that' - it wasn't exactly subtle, but it would get the expected results. "MISS RARITY, WE WOULD APPRECIATE IT IF YOU WOULD REMAIN QUIET FOR A MOMENT."
The unicorn instantly stopped all work, instead staring at her new guest with what could only be described as a mix of terror and awe. The Princess glanced around and coughed, then broke the silence.
"I apologize for doing that - I've been trying to use it less and less. Still, I needed to get your attention somehow."
Rarity still hadn't quite recovered from it, though. "W-what do y-you want?"
"What I want is simple, Miss Rarity - I wish to help."
"O-of course! Anything you'd like, Princ- wait. Help. You... want to help me? You don't actually want anything in return?"
"Correct. I thought I made that clear?"
"Oh, you did! I just wasn't expecting it. If you wish to help though, I suppose we should set to work."
Luna did her very best to fulfill her role as Rarity's assistant - the Princess paced about the room as she cut, carried, sewed, and measured multiple things at once, each section eventually floating across the room to the master seamstress herself, Rarity watching in awe during down-time. Having Luna here was like having a small army, and what normally would've taken multiple hours simply took one instead - Rarity could carry multiple things with her magic, sure, but it was clear that the Princess had a much deeper understanding of magic than most. She had never imagined one would be able to work at the frenzied pace Luna was capable of. The Princess almost seemed to be in multiple places at once - at any given moment, she was carrying something to Rarity, posing for her (reluctantly) with one of the outfits on, or doing some work of her own. The shop was a flurry of fabrics, needles, and threads, and Opalescence made sure to stay in Rarity's bedroom, far away from the ensuing chaos. At last, the final piece drifted over to Rarity, who quickly added it to the dress and threw it atop one of the mannequins.
"We're... we're done! And ahead of schedule, no less!" The unicorn glanced at the clock, and gasped, a smile quickly spreading across her face. "Far ahead of schedule! Oh Princess, I would've been up all night if you hadn't shown up, and even then, I don't know if I would've finished it all! But it's a good thing you did show up, because we gotitalldoneandnowIcangetsomesleepbeforeIhavetogetthesedeliveredIdon'tknowhow-"
Luna laughed and placed a hoof on Rarity's mouth, shutting her up. "You're rambling, Miss Rarity."
"My apologies, Princess. I'm afraid I got excited. I mean... finished early thanks to help from royalty! I've never seen such fast work!"
The Princess blushed, tapping a hoof against the floor. She didn't receive many compliments, not even from her own sister. "It was the least I could do, Miss Rarity. And please, call me Luna."
"Oh, if you insist. Now, Luna my dear, will you be staying for tea? I think we both deserve some after all that, and I wanted to show you around the place a bit - you are my guest after all."
Luna weighed her options and glanced at the clock - she still had time to spare. "I suppose I can stay for one cup of tea, Miss Rarity."
The unicorn beamed upon hearing that, and if Luna didn't know any better, she would've guessed that Rarity was an expert with food, not with a thread and needle. It seemed just a scant few minutes had passed by, and already she found herself seated at a table and sharing stories with Rarity over a cup of tea. Given her tastes in high fashion, she had been downright shocked that Luna often turned down going to many of the gatherings in Canterlot - after all, such a thing was a dream-come-true for her. "Not one? Ever?!"
"I haven't been to any since... oh, I don't know... a little over a thousand years ago? Like I said, Celestia was always into that sort of thing. I just liked getting some peace and quiet, which usually meant staying in the library."
"Bah, you're just like Twilight. Nose stuck in the books, and too busy to know what's going on outside that."
Luna narrowed her eyes at her, to which she nervously glanced about and quickly corrected her callous error. "Er... no offense or anything, Princess."
"None taken, Miss Rarity." Still, Luna did have to admit that she had a point - both her and Twilight Sparkle had an awful lot in common, even if neither wanted to admit it. A quick glance at the clock showed that already an hour had slipped away, and Luna stood up to make for the door.
"You're leaving already, Princess?"
"Yes. I still have some other places to be before the night is over. You know how it is, deadlines and all." Luna grinned and winked at her, and Rarity simply nodded knowingly.
"Still, you will come back another night, won't you? We could have another cup of tea, or share more stories!"
At that, however, the Princess smiled and eagerly nodded.
"Wonderful! Have a pleasant night, Luna!"
"Don't worry, Miss Rarity. I'm sure I will."
A smile on her face, the Princess departed into the night once more. She was beginning to run out of time, and still had so many places she had to be, but she would make it - time had the tendency to work in funny ways for her. Wings outstretched, Luna took a leap, and took to the heavens once more, leaving Rarity watching and pondering the turn of events. After all, friends with royalty? She couldn't wait to see the look on Hoity Toity's face when she told him. Luna, however, already knew her next destination - Sugarcube Corner.