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// A Royal Imperative 
// Story: Postgraduate Work 
// by FanOfMostEverything 
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Celestia frowned. This was in itself a fairly unusual circumstance. She could maintain a mask of warm neutrality through even the longest winded, most pointless audience the Day Court could throw at her. This was different. This mattered.

"Sister?"

The gentle question shook Celestia out of her own head. Quick as a sunbeam, she took stock of the situation. She'd been pacing outside of Twilight's old suite, reoccupied while the new princess's role in the nation's governance was being determined. A warmth in her horn told her that, driven by centuries of habit, she was setting the sun. And here was Luna, looking at her with concern. Celestia brought up her typical, placid expression, knowing it was far too late to disguise her worry. "Good evening, Luna."

Luna gave her sister a perplexed look. "Have you been here since you dismissed your court?"

"No." Celestia avoided her co-ruler's gaze.

"Have you been searching for Twilight Sparkle since then?"

Princess Celestia, master politician, unparalleled negotiator, architect of Equestrian supremacy, found herself utterly tongue-tied. "Uh, er, well..."

Luna grinned, her eyes twinkling with amusement. "No need to be embarrassed, Sister. You have been as a second mother to her. It is only natural that you would feel a mother's concern."

Celestia relaxed, her rictus becoming an actual relieved smile. "I don't suppose you know where she is?"

Luna nodded. "She was waiting outside my door when I awoke this eve. She asked how she could reenter the Realm Transcendent."

Celestia's eyes widened. "I see..." She looked to the western horizon, seeing through the walls of the castle to her descending charge. "The day is almost done. Can you handle it from here?"

Luna pouted. "Have you already forgotten? I've had to shuttle that overgrown firecracker of yours across the sky for most of this week!"

Celestia has the decency to blush. "Learning from me is something familiar to her, something to keep her hooves on the ground."

"Something you can use to pretend your relationship with her has not changed." Luna's expression soured. "She's earned her wings, Sister. You need to let her spread them."

"She's too powerful to let her experiment freely," Celestia protested. "One foalish mistake, and she—"

"She is the Bearer of Magic," Luna interjected. "If she cannot be trusted with such power, then who?"

"Well..." At that moment, the golden aura around Celestia's horn dissipated, an indigo veil over Luna's taking its place. The elder sister grinned. "You seem to have everything in hoof. 'Kay thanks bye!"

Before Luna could respond, Celestia imploded, receding to a point of brilliant sunlight before shooting heavenwards, the ceiling no more an impediment to her than the walls were to her sight.

Luna sighed. Teacher and student had more in common than either realized. "And now I have to deal with both of them." Shaking her head, she made for the audience chamber. The moon needed raising, Night Court convening, and her subjects' dreams defending. The other alicorns would have to sort out their personal issues themselves.

Celestia manifested in the misty realm "above" Equestria. No rising pegasus could reach this place, but it had borne witness to a truly glorious ascension.

The ascender wasn't far from Celestia's entry point. She found Twilight watching an image like those the sun princess had conjured on the cusp of her student's transformation. Her hooves muffled by the mist and the non-matter of the realm's surface, Celestia snuck up behind Twilight and watched alongside her.

The scene was familiar to both, the entrance exam that had been the first step in Twilight's journey. The two princesses watched silently as uncontrolled arcane power surged forth from the younger Twilight, threatening to consume her until Celestia intervened.

The window to the past vanished. Twilight sighed.

Celestia chose to intervene once more. "You've come immeasurably far since that day, Twilight."

The newest princess jumped. She flapped her wings to slow her descent, giving her time to catch her breath and regain her composure. "Pri– er, Celestia!"

Celestia smiled. "I didn't mean to startle you."

"No, no, it's fine." Now facing her mentor, Twilight gestured behind herself. "From the rainboom to you calming me down, my memories are just one big, purple blur. I wanted to fill in the gap."

"I see." An anxious knot Celestia hadn't even noticed loosened. "Are there any other gaps in your knowledge I could help you with?"

"Well, for one, what is this place?" Twilight flared her wings, trying to encompass the whole misty expanse in the gesture.

Celestia looked off into the distance. A few visible memories flickered in and out of existence as her nostalgia made itself known on the impressionable landscape. "Ancient pegasi called it Whinnysium. Diamond dog transcendentalists know it as Curvana. Modern arcane scholars have named it—"

"The Ethereal Plane." Twilight looked around with fresh amazement. "A layer of reality with a higher fundamental energy than the material cosmos. It's purely theoretical." She reflected on this. "Well, it was. But that doesn't explain why that spell to display past events only works here."

Celestia smiled, easily slipping back into the teacher's role. "This place transcends time as much as space. All of history is here if you wish to see it, and time spent here rarely matches how long you spend away from Equestria."

Twilight pondered this. "Have you ever left before you arrived?"

Celestia shook her head. "The flow of time may be strange and sluggish here, but it always flows forward."

"Oh." Twilight frowned. "What about seeing the future?"

An image appeared to one side. The two alicorns turned to behold a writhing riot of colors, convulsing chaotically. Once the eyesore vanished, a wide-eyed Twilight asked, "What. Was. That?"

"That," replied Celestia, "is Canterlot one year from now."

Twilight gaped at her mentor, eyes wild with fear. "Discord! I knew he couldn't be trusted." Her horn shone with power. "I'll get the girls and—"

"Twilight!" A hint of amusement entered into Celestia's smile. "That was not the work of Discord."

Twilight tilted her head as she tried to puzzle out this conundrum. "Then what was it?"

"Every possible future that could come to pass, all superimposed over one another. After more than a week or two, the myriad paths of possibility become completely illegible."

"I see..."

"Anything else, Princess Sparkle?" Celestia was all but beaming.

Twilight blushed. "Please don't call me that." She shook off her embarrassment. "I know we haven't figured everything just yet, but I need to go to Ponyville for a few days."

"Why is that?"

"There's a lot I could learn from this place, but not before I get permission."

Celestia raised her eyebrows. "Permission? Twilight, you're a princess of Equestria. The world is your sugarcube. From whom could you possibly need permission?"

Twilight looked at her teacher, utterly baffled. As though explaining that water was wet, she answered, "My friends."

"Oh. Of course." Celestia smiled, pride and a hint of shame in the expression. "Already you have much to teach me." She cut off Twilight's sputtered protests with a raised hoof. "Now, you are more than free to return to Ponyville, but while you're there, I have an assignment for you."

"An assignment?"

"Indeed. You must determine the nature of your royal domain."

Twilight looked blank. Worry spread across her face like fire over a dry prairie. "My what?"

Celestia draped a wing over the younger princess. "Don't panic, Twilight. I would be very surprised if you had already known of such things. In essence, your royal domain is the answer to a deceptively simple question: What are you princess of?"

Twilight frowned beneath her downy white blanket. "Equestria?"

"True," allowed Celestia, "but not what I meant. I am princess of the sun, Luna, of the moon, Cadence, of love. What is your unique sphere of influence?"

"Friendship," Twilight answered immediately, "or magic."

"Are you sure?"

Twilight opened her mouth to reply, but paused, shut it, and frowned. After a thoughtful moment, she said, "Well..."

"Yes?" Celestia prompted.

"It... just doesn't feel right." Twilight scowled. "I hate to use such vague language, but... it doesn't."

"Then it isn't," Celestia said simply. "Remember, Twilight, you are the first pony to ever transform as you did. Luna and I simply were, and Cadence's birth was one in a trillion. Our cutie marks and domains match because we've always been alicorns. With you, it's clearly more complicated."

Twilight sighed. "Great. It's like finding my cutie mark all over again."

Celestia nuzzled her. "I have every faith that you will discover your domain in short order. Now, let's get back to the palace." She grinned. "You still have to pack, after all!"