“Huh?” Luna looked up from her book, her legs kicking up and down across Celestia’s bed as she flipped the pages idly.
“I said, what do you mean we have to be married in a week?” Celestia asked, staring down at Luna. “How can you not understand the impact of your words?”
“I thought you knew this, Tia.” Luna smiled mischievously. “I mean, you were the one that came up with this idea when I started dating all those gentlecolts in past times.”
“Yes, but those laws were created to protect you, not me. What were the chances of my falling in love like you seemed to do every other day? I just wanted to make sure that you were safe.” Celestia's ears pinned back. “I only ever wanted to protect you, Lulu. I couldn’t stand to see you hurt in such a regular fashion.”
Luna closed her book and sat up, gazing at Celestia's panicked expression. “I know you were trying to protect me, Tia. Now I’m trying to do the same. It’s not that I don’t trust Twilight Sparkle. I just want to make sure that you’ll both be happy. Besides, this gives me a chance to tease my older sister a bit for being so protective. I may as well take advantage of it.”
Celestia groaned while Luna giggled. “What are the chances of us repealing this law in the next… Oh, let’s say five minutes?”
Luna tapped a hoof to her chin. “Hmmm... about as likely as our nephew donating his fortune to charity?”
Celestia groaned, closed her eyes, and rubbed under her horn.
Luna snorted as Celestia let her head fall onto the bed. “Oh, Tia, relax. I have a perfectly good reason for not wanting to change the law for Twilight Sparkle and yourself.”
“You have a reason,” came Celestia’s muffled voice through her blankets. “Would you care to tell me what this ‘perfectly good’ reasoning is?”
“But of course, my dear sister! Simply put, if I were to absolve the law now after having it down on the books for over one thousand years, the nobles would riot. They would—rightfully, I should add—accuse you of favoritism and begin to question Twilight’s ascension even more than they already have.”
Celestia looked up to see Luna softly smiling down at her before nuzzling into her neck.
“I know it’s difficult to see right now, Tia, but it must be this way so that you and Twilight can be happy without having to do something drastic.”
Celestia returned the embrace, rubbing her cheek against Luna’s neck. “I know. You’re right.” She drew back and shook her head. “It has been so long since I penned that damned law. I regretfully have forgotten what it consists of, other than the one week from engagement to matrimony.”
Luna’s horn began to glow as a thin book lifted from the bed and floated in front of Celestia. “Once you made your intentions to ask Twilight for her hoof in marriage clear, I went searching for the entirety of the law—and here it is—” Luna opened the book to a specific page “—now let’s see. ‘Marriage involving an alicorn princess: In the event of a Princess asking for and/or being asked for her hoof in marriage, three trials must be arranged before the ceremony can commence. Trial one consists of an extensive background check of the affiance’.”
She frowned at that. “You, er, might want to warn Twilight that one is coming. I remember what a background check revealed about one of my beloved... it wasn’t exactly pleasant. Moving on, trial two states she ‘must walk through fire, to prove her devotion’ to you. ‘Without using a spell’.”
Luna glanced up at Celestia, who had found something of great interest to examine on the ceiling. “Really, Tia? Walk through fire? Really!”
“It was the poetry of the statement. I did not think that any pony would really be forced to do it!” Celestia mumbled, her ears pinned back and a slight flush coloring her cheeks.
“Be that as it may, it’s written here, so Twilight will have to do it… Next time you create a law, think with more than your heart, sister?”
Celestia nodded as she watched Luna simply stare at the thin book. “So, what is the third trial? It can’t be that bad… can it?”
Luna glanced up and shook her head slowly as if Celestia were a creature which she had never encountered before. “Celestia, werest thou intoxicated or otherwise inebriated when thou penned this law?”
“What do you mean, Luna?” Celestia frowned. She hadn’t had more than a few glasses of wine in... Oh my, how long had it been? And the idea of being high? She couldn’t even envision it.
Luna raised an eyebrow. “You really have no idea, do you? Yes, I know that you wrote this over a thousand years ago, but really, you have no idea whatsoever. You wrote this as the third trial, didn’t you?”
Celestia smiled a bit nervously. “If I said no, would that be a bad thing?”
Luna looked at Celestia and shook her head sadly. “You truly are clueless, aren’t you? For the third trial, Twilight will have to spend a day as you.”
Celestia stared at Luna, her eyes wide with her mouth falling open. “Luna, I’m really starting to wonder if I might in fact have been been drunk or high. How in Equestria is that even supposed to work?”
Luna shrugged as she flipped through the thin book. “There appears to be a spell here. Obviously, you had a plan when you wrote this, sister, and it is my duty as Co-regent of Equestria to fulfill every word.”
Celestia covered her head with her forehooves and groaned. “Why must you choose now of all times to be a normal little sister, Luna?”
Luna giggled at Celestia's muffled whine. “Well, my dear Tia, it’s not like I had the opportunity to do so a thousand years ago. Most of the time you were too busy trying to rule all by yourself that it seemed like you had your head up your… Well, anyway. let’s just consider this me making up for lost time in one go.” Luna nuzzled against Celestia's head. “You’ll give me this won’t you, big sis?”
Celestia lifted her head and gazed into Luna's eyes before frowning.
Luna's ears pinned back against her head. “Is there nothing I can do? Please, Tia, don’t be angry at me.” She moved her head closer to look Celestia straight in the eyes.
Celestia watched Luna become more panic-stricken as the moments passed. When she felt that Luna had learned her lesson, she leaned forward and flicked the tip of her tongue over Luna’s nose; Luna pulled back quickly, her muzzle scrunching.
Celestia laughed at her sister's expression. “Oh, Lulu, you’re just so easy. Sometimes there’s nothing we can really do about the law, at least not this time. Though I do hope that we can endeavor to change it before you fall for a young colt or filly. After all, the poor thing’s going to go through a wreck of nerves anyway, falling in love with the Princess of the Night. The least that I—as your big sister—can do is make sure that they won’t have to go through an extensive background check as well.”
Luna sputtered a bit, then shook her head. “I hate that you made your point. So here’s how it’s going to go: Twilight has three trials that she must complete before you may take her for your bride. Exactly one week remains from four hours ago in which she has to perform these three trials. I suggest that we find a pony to complete the background check during this time. That way, she won't be so anxious when she finds out about it, since she will have already finished the other two trials. I also suggest that you hire a wedding planner, and an expert seamstress to create a beautiful wedding dress in less than a week.”
Celestia’s ears perked as she heard the fern rustle in the corner. “Luna, did you hear—”
Celestia was unable to finish her sentence; a pink earth pony burst out from the fern. Celestia and Luna both jumped back, their wings flaring.
Pinkie Pie danced in place, her whole body radiating excitement. “I heard somepony say wedding! Who’s getting married? Why wasn’t I told? Tell me, tell me, tell me, tell me!"
Celestia glanced down at Luna who was just staring at the vibrating Pinkie. “Well, Luna, you did suggest that we should hire a wedding planner. I truly don't think there is any other pony in Equestria that is as capable—or at least, enthusiastic—as Pinkie Pie is here.”
Luna blinked a couple of times, then nodded. “Y-you may be correct, sister.”
Celestia let her wings fold back against her sides. “Pinkie Pie, I am not entirely certain how you got here. Twilight says that I should just ignore it, that it’s just Pinkie being Pinkie. I suppose I should believe her. After all, what kind of fiancé would I be if I didn’t believe my future wife?"
For a long moment, Pinkie Pie didn't move at all. If Celestia didn’t know any better, she would have thought she’d accidentally broken the pink earth pony; then, all at once, Pinkie leapt into the air with a burst of confetti, her mane and tail seeming even more fluffed up and curly than usual. After her long hangtime in the air—during which Luna began searching for invisible wings—Pinkie landed back down on the floor.
"Oh my goodness, you mean that you and Twilight are getting married? I knew that you two were dating, and I knew I wasn’t supposed to know, but I still knew the third time that Twilight didn’t answer her door, I decided to follow along after you, and you two make such a cute couple with her curled up to you while reading a book as you just happily watch the sky! Did you ask her or did she ask you? It’s very important for the party planner to know who the groom is, after all, so how long do I have to plan this wedding date? Is it going to be super-quick like Princess Cadance's was? Oh, I hope we don’t have to deal with the changelings again. They really ruined everything last time."
Celestia watched, stunned, as Pinkie Pie bounced around and quickly asked several different questions, all seemingly without needing to breathe. She looked at Luna who just shrugged.
“Must be just ‘Pinkie Pie being Pinkie Pie,’ as your dear fiancé says.”
Celestia gently placed a hoof on Pinkie’s muzzle. “Yes, Pinkie. Twilight and I are getting married. I asked her, so I guess that would make me the groom. No, I do very much hope that the changelings will not be involved this time, and if I have any say in it, I wish to never see them again. As for how long you have to plan the wedding... because of a foolish law I wrote over a millennium ago, you have exactly seven days as of four hours ago.”
Pinkie stared at Celestia open-mouthed once Celestia had removed her hoof. “Wowee, only a week to plan out a giant royal wedding that has to be absolutely perfect? I’ll have to cancel all my other engagements. This is going to need my full attention!”
With that, Pinkie reached into her mane and pulled out a small green alligator. “Gummy, cancel all my other engagements. This is priority numero uno!” Pinkies stared down at her pet, which stared up at her and blinked a couple of times. Pinkie beamed down at him—Celestia assumed it was a ‘he’—and nodded.
“Yes, exactly!” She picked him up and stuck him back in her mane before smiling up at Princess Celestia. “Don't worry, Princess, you can count on me. This wedding is going to be just superrific!”
Celestia blinked just once, then all of a sudden Pinkie Pie had vanished. She turned to Luna, who was just looking around the room. "Did you…?"
Luna shook her head. “No, and neither did you if you value your sanity. Now as we were discussing earlier, which of the trials do you plan on having Twilight complete first?”
Celestia sighed, running a hoof through her mane before sitting down and placing her head between her hooves. “I don’t know, Luna. Are you sure that this is all one hundred percent necessary for Twilight and I to be married?”
Luna clicked her tongue a few times, then finally shrugged. “Of course, its entirely possible that this is all for naught, but consider this, Tia—what if one of the nobles were to discover this law, ancient as it is? Nobles such as our dear nephew Blueblood.”
Celestias head shot up, her pink eyes wide. “I... had not even considered the possibility... that would be just like him to do so. You remember the fuss he put up when Twilight became an alicorn to begin with. He swore up and down that I was exhibiting favoritism and that if any pony was to be made an alicorn, it should be him. On the faint chance of him finding out, I could never do that to Twilight…”
She nodded. “Very well. The law shall go forward as it is written. Since Twilight and I have kept our relationship mostly secret, I would like to deviate away from the numbered trials just a bit. I agree with you that it would be best for the background check to begin immediately.”
Luna closed her eyes briefly. “That leaves trials two and three. I would see to them both myself, however—” she opened her eyes“—number two on the list is for Twilight to prove her love by walking through fire. The problem is, there’s supposed to be an audience for this—several witnesses need to confirm that she used no spell walking through the fire.”
Celestia gasped, and then groaned. “Witnesses… why did I specify witnesses?” She rubbed the base of her horn and sighed. “In that case, I would prefer to wait until a little later in the week so we have a chance to announce our engagement to the public.”
Luna mimicked Celestia’s gesture as she grimaced. “You realize what that means then, don’t you?” she asked, throwing worry Celestia’s way.
Celestia nodded. ”It means that I really, sincerely hope I have a slow court tomorrow, because I’m about to throw Twilight to the hounds.”
Twilight blinked her eyes sleepily as she looked up at her new fiancé and soon-to-be sister-in-law. She shook her head with a little yawn. “Sorry, Tia. I wasn't expecting you to call me so soon. Is something wrong?” She cocked her head as Celestia bit her lip.
Twilight bit her own lip, a small whimper escaping. “Did I do something wrong? I’m so sorry! Did I break a really important rule about being engaged? Please, how can I make it up to you?”
Unwilling to see her fiancé worrying for another second, Celestia wrapped her large white wings around Twilight's shaking form. “No, my sweet Twilight, it's not your fault at all. This is my fault—a foolish mistake I made over a millennium ago.”
Twilight gulped, snuggling into Celestia's chest. "A mistake? Are you promised to another? A-are we going to have to break up? I don't want that, Tia. I don't want to have to leave you.”
Celestia nuzzled the top of Twilight’s head. “I swear to you, my love, that one thing you will never have to fear is our separation. I love you as much as I love my own sun. No, we won't have to separate and there is no other pony that I am promised to. You must understand. Many years ago, many noble stallions were trying to gain my favor. They felt that the easiest way to do this was through my sister, so they tried to woo her into marriage.
“The fact is that several came far too close for my own comfort, so to protect her and myself, I wrote the law of how marriage must proceed between an Alicorn Princess and her beloved. I never thought in a million years that I myself would fall in love and that it would not be with a pony trying to take advantage of me, so I never canceled the law. Please forgive me?”
Twilight chewed her lip a bit. “A law to marry a Princess? I’ve never even heard of such a thing. But I understand your reasoning for wanting one, especially if Luna’s virtue was at stake. How complex is this law?”
Luna's horn lit up as she levitated the slim book over to Twilight. “Here, you will find the entirety of the law that Celestia wrote so very long ago. I encourage you to read it carefully.”
Twilight took the book within her own magic and cuddled up to Celestia. She opened it and began reading; it didn't take long for her eyebrow to begin twitching, either. Within a few minutes, she had finished the section in its entirety and was just staring at the final page. Finally, she allowed the book to close and looked up at her beloved.
“Celestia... I love you with all my heart, but I must ask you something.”
Celestia smiled, albeit a bit nervously with her ears pinned back. “Yes, my Twilight. Anything.”
Twilight looked straight into Celestia’s eyes… and unloaded.
“What in Equestria were you drinking when you created this law? Calling it convoluted would be kind! We have to be married in exactly a week from the moment you asked me to marry you? How could anypony even plan that big of a wedding in less than a week?”
“Don't worry, Twilight, I got this!” Pinkie grinned before leaping back into the fern.
“Huh?” Twilight looked around the room. “Was that...?”
Celestia nodded. “Somehow she heard Luna and I speaking about needing a wedding planner all the way from Ponyville. Do you have any idea how she appeared from out of my bedroom fern?”
Twilight simply shook her head. “I don’t even question it anymore, Tia. Honestly, I could spend the rest of eternity studying Pinkie Pie and I still don't think I’d understand her. Now back to this law. It seems that the one week thing isn't too big of a deal since Pinkie Pie is in charge of planning, but how deep does this background check go?” She couldn't help her voice squeaking just a little bit at the idea of somepony dipping too deep into her closet of skeletons.
Celestia stroked Twilight’s cheek. “Twilight, trust me—you’re better off not thinking about it. The only pony that will ever see it will be myself, and I do promise it will never be released to anypony else. Not even you, Luna.”
Twilight looked up to see Luna standing behind Celestia with her tongue stuck out. She giggled at the gesture; it wasn't often that she saw the sisters tease each other like this, though it made Twilight smile every time that she observed it. She hoped that once she and Celestia were married, she would be witness to it far more often.
“All right.” She breathed in and out deeply. “So you don’t want me to worry about the background check. There are still two more trials. I’m pretty sure I can figure out how to walk through fire without using the spell now that I’m an alicorn, but I don’t understand how it is even possible for me to spend a day as you. I mean, body-swapping spells don't even exist… Do they?”
Celestia glanced away. “They do in fact exist, Twilight, although they are held within the deepest part of the restricted archives—farther than even Sunset Shimmer dared to go. Many times I’ve thought to destroy the scroll containing the spell to eliminate the chances of somepony discovering that was a simple spell they could use to take my or Luna's spot... our bodies, even. Who would believe somepony that was spouting that they were in fact the Princess?”Celestia shook her head. “But destroying any magic seems such a waste to me, and there could come a time when any spell might be potentially useful, so, like many others, I keep the spell hidden from all but my sight.”
Twilight cocked her head. “Until now?”
Celestia nodded. “Yes. The least I can do before casting this spell upon us is to share it with you. After all, if I can’t trust you with the spell, I could never hope to trust you with my heart, and you know that you already rule over that.”
Twilight blushed while pawing at the floor with her forehoof. “I feel the same way, Tia.”
There was a flash of gold light and a large book appeared in front of Twilight.
“Go on, my dear. I have nothing to hide from you.” Celestia nuzzled Twilight's neck.
Twilight nodded and opened the book. She quickly became absorbed in the many different banned spells that the book contained. It even included the idea that it was possible to turn a pony into a manticore against their will, and that wasn’t even among the worst spells. Twilight shivered; she immediately understood why Celestia had chosen to keep this book under such lock and key.
She quickly glanced at the rest of the spells until she found the body swap one. In the back of her mind, Twilight wondered what had happened to the pony that had written this book, but after glancing at Celestia’s face, she promised herself she would never allow the question to exit her lips. She didn’t want to know the answer.
As she began to read the spell for the body swap she frowned, then looked up at Celestia. “This spell it so simple that any unicorn with rudimentary magic knowledge would be able to cast it without a problem. In fact, I wouldn’t be surprised if a foal just discovering their cutie mark would be able to cast it.”
All at once, Celestia seemed older than Twilight it ever seen her before. ”You're not wrong, my dear—and therein lies its danger. The reasoning behind my having to lock away this book was for far more than just a body swap spell, but that is a story from a long time ago, and one I do not wish to get into now. Forgive me just this one secret, my love.”
Twilight closed her eyes in thought before smiling. “Just this once, Tia. Now, let’s cast this spell!”