Princess Celestia's Most Faithful Headache

by X equals Friendship

First published

In retrospection, Celestia should've known better.

After several centuries Celestia's wish for an intellectual partner without any relationship with her was granted. It came in the form of a twenty-something pegasus scientist with a knack for intellectual pettiness.


Chapter 1

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Disclaimery Disclaimer is Disclaimery

Kokonoe Ayatsuki Mercury from BlazBlue is owned by Arc System Works, Toshimichi Mori and Yūki Katō.
My Little Pony: Friendship is Magic is owned by Hasbro and Lauren Faust.

All in all, it wasn't unusual for Luna to see her sister indulge herself with alcohol.

"Sister? We have another pile for you."

Sure, Luna probably shouldn't be delivering Celestia her mail, it was the duty of the royal attendant, but she could use any opportunity to check on her elder sister.

"Please tell me it's from Cadence complaining about Twilight being friendly with Chrysalis. Please."

Luna smiled unapologetically at her sister, a bottle of wine was levitated from her lips before being thrown to a pile behind her, it wasn't easy to get inebriated as an alicorn, but it looked as if Celestia was determined to try anyway.

"Sadly no. It's from her again, I think this one's thicker though."

Luna said as she dropped the heavy stack of documents on her sister's desk, the title

'The Magitek Theory, draft 75C (pending) by Professor Kokonoe Mercury'

on the first page.

Luna swore she could hear her sister whimper just by looking at it, she lifted the first page and indeed saw it full of words and diagrams from the very beginning.

"Seventy five? Has she really been that many?"

"It's Seventy Five C Luna. She has sent me over THREE HUNDRED revisions IN. TWO. MONTHS!"

Celestia cried in exasperation

"Just how in Equestria does Kokonoe manage to write so much!? And if I don't reply she just sends the next revision faster! The mail service refuses to refuse her service since she's the best costumer they've ever had and now they deliver it to me personally!"

Luna had to refrain herself from chuckling, sad as her sister's hysteria was, it was refreshing to see her not know how to deal with a situation from time to time. And the best part? Celestia had brought this entirely to herself.

It had started as a simple comment she had made when the promising pink haired pegasus with a labcoat had presented her magic theory.

"I'm afraid your study just wouldn't work my little pony, you should try asking a unicorn for advice since they would know better on the practical side of magic, some fields just are meant to some specific ponies."

Perhaps it had been due to the amount of stress her sister had at that time, perhaps it had been due to the amount of projects she had seen at the time, but the slightly rude and dismissive way she had told the pegasus about how her theory wouldn't work has ignited something in her.

And as such, she had begun an open debate to prove the princess she was right.

By sending her investigations straight to her, almost weekly and with every document having a minimum of twenty pages each. The young pegasus has singlehandedly become the biggest headache, and possibly nightmare, the powerful princess of the sun has had in centuries. Luna could swear Celestia couldn't look at a labcoat without having a mild panic spike of the amount of papers she would have to read.

Luna was actually impartial to the mare, her theory was sound if somewhat cynical in the way it analyzed magic as an energy source instead of the emotional receptor they knew it could be. Kokonoe's approach to it was drier, and contradicting to the philosophy of focusing on empathy and understanding to enhance magical abilities, Kokonoe didn't disregard them, she just focused in another aspect.

Celestia could just be somewhat preachy in her stance of magic, way more than Luna ever remembered being, and as such, this made her unable to just disregard everything Kokonoe send her. Call it morbid curiosity if you would, but Luna always awaited the next entry of the mare's theory, if anything, just to see how her sister would react to it.

Maybe she should visit Kokonoe later, to see if she had anything that could catch her eye.

"Oh by the way sister, she also reminded you to cut on your banana ration, something about it all going to your hips?"


Yup, Luna would definitely visit her later.

Chapter 2

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Starlight Glimmer saw her friend pase back and forth across the room as she muttered to herself, occasionally burrowing her face back into the same stack of papers as she had been doing for about an hour, or at least, that's when she arrived to see her.

"The released dopamine is suspected to contain high quantities of ether and.. What.. What am I reading?"

Unbeknownst to Twilight, she had begun to see why Celestia was taking the topics written in Kokonoe's report so close to heart. She didn't even see Starlight Glimmer stay there for about twenty more minutes before walking off to go on with her day.

It didn't disregard the importance of Friendship, but the terms it used reminded Twilight of what her friends had said she sounded like whenever she Nerded Out, only much much worse.

The paper spoke of the importance of pony relationships with one another and made a very sounding comparison to the way Changelings fed, something Twilight herself had once hypothesized only for it to be partially confirmed by Chrysalis, but it was all so...


That's the word she had been looking for. The paper sounded exactly like a case study, as if it was studying the behavior of an ability of an animal, a controlled subject instead of a living, feeling pony, it felt like it was written from the perspective of an outsider of pony society, but it was written by a Pegasus and that, Twilight thought, made it seem just the slightest bit creepy.

"So This is where that thing ended up."

Let it be known, that at that moment Princess of Friendship Twilight Sparkle found it extremely important to inspect the chandelier, for she did not Eep in surprise all the way to the ceiling.

"L-Luna? Dear Faust don't scare me like that!"

Luna gave Twilight the most plain look she could muster, as if to say 'really?', if Discord was here he'd have a camera ready, but he decided it was more fun to watch her sister squirm. Not that she blamed him.

"I see you ended up getting the paper Tia sent you by accident."

At this Twilight blinked.

"Accident? You mean this was Princes- I mean Celestia's?"

Luna looked around the room full of books and took a seat right in front of the book fort.

"Yeah. It's actually the four hundredth paper. She probably received number four o' one this morning."

Four hundred one. Twilight's eyes widened.

"You mean she has the entire collection of the notes of Professor Mercury?"

Luna smirked.

"Current, previous and probably future for a long while. I'm sure you remember the 'meeting' Tia had with the professor. Let's say Kokonoe did not take her opinion kindly and she's been sending any and all progress she has in her experiments to my sister, it's been three months already and it hasn't showed signs of stopping as of now."

Luna took the pack of papers from Twilight's grasp and read the title of it to herself.

"What you're seeing is actually one of her side works. Her main theory is currently number 82-M if I'm not mistaken. I'd say Celestia currently has over a thousand works of her alone if you count the many reference notes she sends from time to time."

Twilight was on the edge of hyperventilating.

If she counted this as the average length it rounded about thirty thousand pages. Over thirty thousand pages and possibly even more worth of pure research by one pony was insane. She had heard Kokonoe Mercury was considered a prodigy in the field but this made Twilight, who was a prodigy herself, be flabbergasted at the sheer amount of Progress this mare was achieving.

"I'm actually planning on visiting her later. Would you be interested in comi-"


Luna would need to teach Twilight about double meanings later, even a thousand years back that phrase was so easy to misunderstand.