When Celestia had told Luna that she had something exciting to show her younger sister, Luna cooled herself out of instinct. There always had been little way of knowing whether any surprise that Celestia produced would be good or ill. Studying the behavior of her elder sister often gave Luna enough of an indication of what its nature could be, but more often than not the behavior of her sister was blinding. Celestia only operated by being totally transparent, albeit unknowingly, or by keeping everything about her impossibly tucked behind whatever face she wanted to show. It was a habit of the crown that Luna had never let herself acquire.
To judge a situation before entering was always wise, and Luna let herself remain earnestly calm as she strolled into the throne room. It was Celestia's favorite place to meet, even when she only wanted to speak over something apolitical with Luna. All the windows were bright with the sunlight that cast their colors upon the walls and floor. It was certainly a setting that matched Luna's relatively calm state, but that was not to say there was never a flutter of anxiety lurking in her.
Celestia's surprises always gave her such a coil of apprehension somewhere within her. Always did Celestia say how her plans were perfect and that everypony would simply adore her efforts as she did her refined prance about the castle halls. It was always her sister who was quick to celebrate preemptively and pepper their every conversation with her proclamations:
'Oh Luna, you'll simply adore it!' she had heard earlier this week. 'Every mare in the city is going to want one, so I just had to get you one too!'
'Just wait until the servants bring it back! You'll simply adore the look! I believe that it is what the fillies these days would say is very 'fetch' as the saying goes!'
Luna counted herself lucky to have gotten to the throne room first. The sole throne of Equestria was empty and waiting for her, appearing as elegant and inviting as ever. It was always a strange sight to see Celestia apart from it, for the thing was practically her lover with how attached she was to the imperial seat.
Settling in with a quiet hum, Luna drew in a deep breath. She dare not try and slip too far into a state of meditation, for she would likely be able to only have a few moments to herself before somepony would see fit to interrupt her. In that regard, both Celestia and the castle servants treated her identically to how one would gawk and chatter at an owl in a petting zoo, not knowing that the poor creature perching with their eyes closed would appreciate it ever so much if they were observed with respectful silence.
Thankfully, the day was a lovely one, and the Equestrian throne's red cushions were even lovelier. Celestia was nearly married to that chair, and because of that, she only permitted the comfiest cushions to be there. They were perfect for enjoying a short, cozy rest with how soft and oddly squishy they were.
Luna had barely gotten a few moments to settle in properly when Celestia trotted in. Her hoofsteps rang out so much and her gait was so obvious that Luna's posture immediately tensed with readiness for conversation, and she realized that she had lost track of where she was in the song she was humming.
"Oh, perfect!" Celestia says, her ever-present smile soft and plain. "I was just about to send somepony to fetch you!"
Luna offered a small shrug, keeping her expression noncommittal. Her gaze drifted curiously to the box that Celestia was balancing upon her back. It was wrapped with a pink bow, and the paper it was wrapped with was a soft orange about all its wide corners. Everything about it screamed Celestia's doing, for the box was all done up in her favorite colors.
"I have been waiting for you, Tia. What did you wish to share?" Luna asked, keeping her gaze carefully upon the mysterious box.
"Well," Celestia said, smiling wider, "I just had to show you what I got for the Summer Harvest Parade in Baltimare!"
Dangling from the box was a tag, one that told Luna what the gift would be. Ever since Tia's precious Twilight Sparkle had moved to Ponyville, Celestia had taken advantage of the Generosity Bearer's career and added Rarity to her rotation of commissioned designers. The work of Miss Rarity blended in with the usual roulette of ever-the-best, most popular, and highest-standard-only wardrobe that Celestia was such a stickler about maintaining.
"Sister, the Summer Harvest Parades shall not be upon Equestria for a few more weeks—"
"Oh, silly Luna. That attitude is pish-posh." Celestia was beaming, her mane afloat with an overdose of cheer. "Think of how much fun things will be if we have everything ready beforehoof! Every tailor in Equestria's heartland will be flooded with orders once the celebrations are closer, and it's the early bird that gets the worm."
Celestia was one to talk about being early when she always bemoaned getting out of bed on time for each coming dawn. When it came to tailors, at least Tia had a point.
Luna said nothing in return, only giving a tiny, half-hearted nod to show that she was listening to her sister.
Seeing Luna's reaction, Celestia tutted and her mane waved and sparkled extra insistently to go with her next words. There were usually little betrayals in Celestia's demeanor, ones that their subjects never picked up on, but Luna knew how to spot. In them, she was able to read keenly how her big sister felt behind that unshakeable, blasé serene smile. Though, the excitable whirling of Tia's mane aside, Luna need only hear her sister's voice right now to know that she was excited.
"Now, there's no need to look so down. Just wait until I show you what I got, it'll turn that frown upside down. You and I are going to be the talk of Equestria!
Luna blinked, suddenly feeling very confused about why Celestia thought she was frowning just because she wanted to show that she was a good listener. Stars, did she need to have her muzzle bearing a freakish Grassgrow smile at all hours for her sister to know that she was alright?
"Tia, I'm quite—"
"Shh," Celestia hissed in an abrupt, exaggerated stage whisper. She was smiling widely, unaware of how Luna just absolutely wanted to wilt at the interruption. "Just wait until you see them!"
Before Luna had the chance to add anything else in, Celestia unfolded one of her colossal wings and scooped her box off her back. Then, she sat down and transferred it from where it rested on her wing to her forehooves.
Luna watched as Celestia at last lit her horn dimly and began to unravel the bow. It was only when the lid of the box was raised toward Luna did she feel the tide of mixed emotions coming back to her once again.
Celestia said that what she got was for both of them, but how well was she going to incorporate Luna's desire for a suit into something that needed a shared order and box? If Celestia ever let Luna decide what would be worn to the events they had to attend, Luna would try and get them both amazing pieces. As nice as surprises could be, when it came to something personal and meant for preserving like clothes, there was no reason not to ask Tia just what might she want in terms of cut, color, and if she wanted a gown at all.
Maybe it would spoil things, but as much as Luna loved surprises compared to her sister, it would be worth it to know she got somepony something that they would take genuine enjoyment in. It was like when catering duties fell to Luna: she would make sure to summon a diverse parade of culinary experts and establishments from all over Equestria and beyond to replace the usual trends of Canterlot. But no matter how many kinds of cooks from all the nations in the known world she would send a scroll to, Luna would always ask Celestia if there was anything she wanted. It could be anything: a certain wine, an exotic pastry, or a more modern dish that Luna had yet to know of.
She did it all for Celestia because she didn't want her sister to ever know what it was like to know how it felt to have the grandest of celebrations all around you — and for you to be the one drifting as a forgotten satellite.
The first item that Celestia pulled from the box was a hazy white dress. It pooled like mist in her hooves and looked like the chicest of blouses made long and proper by gown-length standards. There was a defined waistline to it, and whatever was cinching it was embroidered with a decidedly Trottish design. Every bit of it shone with something Romantic — in the big 'R' sense of the word — and pulled straight from one of the paintings of Waterhorse. It was a lovely dress for Saddlespeare's Ophelia or the Mare of Shalott, just nothing that Luna would ever wear.
On the thought of it as a blouse — Luna could see it as a lovely, androgynous loose blouse if there were no skirt to it. But as a dress, it certainly looked like something Celestia would wear — albeit more than a bit short. Luna wondered why the world of tailors was going to bother with dresses if they were going to just get shorter and shorter.
"I am reminded of the fog over the mountains," Luna replied quietly, letting her eyes follow the designs.
Celestia smiled with greater excitement. "Oh, don't contain all your surprise. Just look at this fabric. I was assured by one Miss Sassy Saddles that this kind of style would absolutely blow everypony away, don't you think?"
"Perhaps," Luna murmured, that familiar uncertainty still dancing within her chest.
Her thin gold aura reached into the box, where Celestia withdrew the rest of the contents. Out came another dress, one that was identical in design to the piece that Celestia had just produced except for one thing. This one was longer, its train more sweeping, and its waist an illusion. Luna recognized this feature immediately: her big sister always commissioned dresses with the false appearances of midsections because her noticeably chubbier figure meant she had nothing resembling Luna's leaner frame.
Such was a popular feature in mare's fashion, where Celestia had always been praised as the paragon of beauty no matter her size, and Luna's dark looks and natural hourglass physique were given no second glances.
And it could only mean one thing for Luna.
"Oh, see, I knew I could make you speechless!" Celestia cheered, waving the two gowns back into their box hastily. "Just think of how adorable these will look! According to Twilight, it is quite hip with the foals to call this sort of thing a 'twinsies' look. We'll be twinsies!"
Luna's smile was as tightly sculpted as glass accents on an ornament and twice as fragile.
"Tia?" she called softly.
All she could do was stare as her big sister clapped her forehooves together giddily, the shoes on her hooves creating an unusual ring. Leave it to Celestia to be caught up in her spell of fashion and all the usual subjects of mare-talk.
"Tia?" Luna called again, raising her voice only slightly. She hoped she didn't sound too rude.
"Hm?" Celestia slowly looked her way, wearing a face of utter confusion. "Why are you being so loud?"
"I'm sorry, Tia. I just thought..."
Was that suspicion in Celestia's eyes? It was hard to tell, and Celestia usually let her emotion out as just that: faint, bottled glimmers in the backmost parts of her eyes. To see her sister so unusually active in her happiness was a sign of how much this modern game of matching gowns meant so much to her.
"You thought what, Luna?"
Why did it always have to be things like this that mattered to Celestia? Pomp, preening, and party-things may be called social games, but there was no fun to them, only a misnomer. Yet propriety was high on Celestia's value pedestals and knew that to expect care about the things she cherished, she had to try her hoof at what her sister cared about, at least sometimes.
Oh Tartarus, sometimes she just wished it felt more like a choice. Was it not supposed to be a choice?
"You and I... we talked about a suit for me at the last event, and I was hoping that you might have ordered it for this one."
Celestia raised one eyebrow ever-so-slightly. "You actually wanted a suit?"
Luna wasted no time in nodding eagerly, and the sudden fuzziness in her heart made her feel like her whole being was lighting up. "Oh, yes! A splendid suit! There is this mare's boutique not far from the castle, and their pieces are incredibly eye-catching! I read that they even had the great modern philosopher Imogen Canter ordered their suits to be sent to her home in Coltigsberg! Such is the longevity of their business."
"I... Luna, it's too late for that now. When did you say it was something you definitely wanted?"
Was Celestia just being Celestia, or did Luna pick the wrong time to mention Imogen Canter, knowing Celestia had no love of the thinker? And here Luna thought that somepony might genuinely appreciate the tidbit as simple trivia.
"Three times since we arrived back from Manehattan," Luna replied immediately. "I asked if you wished for me to write it down for you."
"Hm, well, Luna... I must have been very busy. And it really is too late now to have anything else ordered from Rarity. Besides, it wouldn't have been a surprise if I had gotten suits for us... and I thought you liked my surprises."
"Tia, I..." All of Luna's hopes went uncaught by the words she stumbled to string on.
"Just think about what everypony would say if only one of us wore Rarity's designs to the festival. To hurt her feelings would hurt those of Twilight too. I've already told and written to all my friends about how adorable we'll look in our matching outfits, and if we don't go through... well, Luna it's going to reflect poorly on our subjects if we don't have that harmony."
"Must we always stick to your themes? Why not have each of us get what we truly wish?" She didn't want to sound too pleading, but the emotion inevitably pooled in Luna's words.
"That would be improper, and especially for our station," Celestia replied with a solemn shake of her head, the curt kind given to pesky subjects with silly petitions.
"Tia, please—"
"Our subjects' thoughts about us are of the utmost importance. We wouldn't them to think that we were fighting, now would we?"
"What if we both wore suits next time?" Luna blurted, her wings extended slightly in obvious, cautious hope.
"You know I don't like the newfangled tomcolt styles..."
"But I do!"
Celestia flicked one of her ears to the side. "I've never worn a suit."
"Well, what if..."
"Luna," Celestia breathed in a tone that was stiff with motherly scolding. "I hear you plainly. There's no need to bombard me with what-ifs. You know how I feel about those."
Luna loved her sister, but she hated that tone, and even more, she loathed that Celestia could not recognize that she used it on her own sibling.
"We can talk about a suit for you for the next event."
"Is that a Big Sis Promise?" asked Luna quietly, looking up to Celestia with damp, wide-eyed expectance from under her forelock. Her dark, rich mane waved with a light wistful flick.
Closing her eyes, Celestia nodded, though the gesture looked so much like relenting. What was it that Celestia felt she relinquished? Why must she feel that she had done so at all?
And would this next-time to-be end up like all the other 'next times' that Celestia had promised her? Granted, none of them had ever been a Big Sis Promise, but every next time had never been. These were the kinds of things that happened only every time.