Luna levered her eyes open through pure force of will, cracking the gunk that had built up on her eyes over the course of a good day's being passed out through only the greatest of efforts. It was instinct that drove her from her coma—she could feel the moon's eagerness to rise as a pressure at the base of her horn, not entirely unlike the pressure in her bladder. What she really wanted to do, right at that precise moment, was to tell the moon to take a thousand-year adventure into the Oort cloud, but... everypony would complain and probably panic, and use words like 'unilateral' and 'tyrant' and 'ecological catastrophe', and it would just not be worth the trouble. Instead, she took the easy route once again, lifting her head and raising the moon with her eyes screwed shut.

Just like every night, the act of raising the moon was more effective than any cup of anything had ever been at waking the dark alicorn up and, not for the first time, she cursed that fact through a pounding headache. After a brief trip to the temporarily-elevated Little Goddess' Room, she dissolved herself into a mist and wisped herself downstairs—hoofsteps made her head hurt worse.

What she found down there was alarming. Twilight sat at the table with the charming abstract equine bust, and she was surrounded by crumpled papers. No—she was nearly buried in them! Her head stuck out from the center of a piled cone of the stuff, and her horn glowed busily. She was clutching in her magic a broken quill that skittered back and forth across a fresh sheet of paper like a mouse being chased by a cat, but she was staring at no discernible spot in particular, apparently unconcerned about the quill's scribbling—though it looked like she hadn't remembered to dip it in her inkwell for quite some time, so that perhaps did not matter so much. The sound of grinding teeth seeped into Luna's ears, and she winced. That made her head hurt worse too. Still...

She gingerly laid a hoof on Twilight's shoulder (though not before putting together a few cursory wards--she was hungover, not stupid). To her surprise, though, instead of some variety of manic, maniacal, or otherwise extreme reaction, Twilight's shoulders merely slumped, and her quill fell to the tabletop.

The unicorn turned to her, and it was the last thing Luna was prepared for. Twilight's eyes were bloodshot from being rubbed, and accented with dark bags. Fresh tears were brimming as she fixed Luna with her stare, and—oh stars—her bottom lip was quivering. Over the top of the unicorn's disheveled mane, Luna could make out the first three words of Twilight's letter.

Dear Princess Celestia,

Luna's heart sank. The rest of letter was meaningless scribbles and a crude drawing of three ponies, but that hardly mattered. She gathered Twilight up with her front legs and wings, gently patting down the stray frizzies of the unicorn's mane with one hoof. Twilight clung to her fiercely once she was given that permission, and Luna let out a quiet sigh. Damn Celestia anyway... and damn me.

Luna stayed still for Twilight, and Twilight repaid her with a few more tears, which disappeared against Luna's dark coat. Finally, Twilight raised her head, sniffling and wiping the back of one hoof across her muzzle. When she spoke, it was very quiet.

“I'm sorry, Luna, I'm being silly... I was fine when I woke up. A little... um.”

Luna raised an eyebrow, but she paired it with a gentle smile for Twilight, “Um?”

Twilight chuckled weakly, though it was still halfway hysterical, “Um is about right, yeah. But I've been by myself all day, with nothing else to think about,” she looked up at Luna, mournful and deadly serious. Two pieces of crumpled up paper were still stuck in her mane.

“I think I got a little carried away.”

***

Luna had manifested a hoofkerchief and immediately set to cleaning Twilight up, dabbing daintily at the smaller mare's eyes. The attention seemed to calm Twilight down almost immediately—she seemed to reach a sort of zoned-out serenity as Luna brushed out her mane.

Luna allowed herself a small smile. Twilight was certainly cute. She would also... hm. That was a little problematic. Luna wasn't entirely sure what Twilight was now, honestly. The mare had been actually trying, carefully and a little clumsily, to put the moves on Luna last night. Well, maybe more than a little clumsily; she'd obviously gotten her hooves on some laughable tome, but... the flashes of herself in between the anonymous book's instruction had made the whole thing endearing. It had seemed like she was about ready to give up on the book's instructions when... when Celly interrupted them. When they'd both thrown themselves at the elder goddess.

The smile faded from Luna's face. Looking down, she noticed that she had been combing the same lock of Twilight's tail for the last half-minute at least, though Twilight didn't seem to mind, or possibly even have noticed. When she stopped, the unicorn awoke from her pleasant daze and looked up at her quizzically.

Yes, she was certainly cute. Luna took a deep breath.

“My sister will have returned to Canterlot. We should follow her.”

Twilight nodded, silently and solemnly, which only seemed to make her more adorable. Luna suppressed a sigh at her own twitterpated self, then abruptly dissolved into the glittering, quietly chiming mist. She swirled around Twilight, contracted, and shrank them both to a point. They disappeared with a quiet 'poit'.

***

The guards outside Celestia's chambers were already nervous. Most ponies wouldn't have been able to tell, but the pair shared glances frequently, and the pegasus couldn't seem to stop himself from re-adjusting his wings every few minutes. For the royal guard, this constituted a screaming panic; if either one of them had been remotely in the mood for it, they'd have shared a self-conscious grin, thinking about what their drill instructor would have done to them for being so lax.

But they weren't, so they didn't; too busy panicking.

In any case, when the air was rent by an incredible, ear-splitting noise, they both nearly jumped out of their armor. If they'd had the education to know, they would have recognized the sound of an incredibly powerful teleportation impacting an even more powerful ward. What they heard, so far as they could tell, was a gong crossed with a plucked spring--”CRASH-SH-SH-SH-Sh-sh-shhh...”

Twilight and Luna popped into existence in front of them, and Luna already had her head clutched between her hooves, her eyes screwed closed and her teeth gritted. Twilight started toward her, but Luna waved her off, “We are fine. We will be fine.”

Foalish and more foalish; she hadn't hit one of Celly's wards like that in at least three thousand years. Twilight didn't look particularly convinced either, frozen as she was with her hoof half-out to Luna. The dark alicorn put her forehooves on the ground and forced out her best reassuring smile. It was a rictus, she could tell; she couldn't seem to unclench her teeth. Twilight was clearly still unconvinced, but she lowered her hoof, and so it would have to do.

The guard on the left cleared his throat. Strangely, he did not seem to find the sudden presence of the two mares very calming, and Luna made a mental note to quietly resent that at a later date. For now, she had bigger zucchini to fry. Fixing the guards with her very best royal regard down her muzzle, she arched one eyebrow and jerked her head to the side, indicating the stairs down. They got the message, and gladly marched off at about triple-time.

Luna waited for the jingle-jangle of their armor to fade before rapping smartly at Celestia's door, though to Twilight it looked rather like a fairly vicious kick.

“Sister?”

No answer.

“Sister!”

Still no answer. Luna growled under her breath and pounded at the door. As she opened her mouth, some blessed instinct told Twilight to cover her ears. It had been a foreshadowing ringing in her ears, and for a moment, Twilight worried that she had been spending too much time with Pinkie Pie. The thought was shortly blotted from her brain though, even through her hooves.

“SISTER! WE DEMAND THAT THOU OPENEST THIS DOOR AT ONCE, OR WE SHALL... WE SHALL FIRE THE ROYAL PASTRY CHEF!”

Twilight glared at Luna, hissing under her breath, “Petit Four doesn't deserve that!”

Luna looked blankly back at Twilight for a long moment before sighing. “Twilight, may we suggest that thou never playest poker?”

“What--” Twilight plonked back down on her haunches, puzzled and upset; “Why does everypony tell me that?”

Luna didn't answer her; she had returned to inveighing the door and the princess presumably behind it. After a long tirade—Twilight wished she had her notebook, she was sure one or two of the things Luna said implied some very large gaps in the standard history books—Luna had apparently exhausted herself, resting her nose and horntip against the door and panting. Quietly, she tried one last time.

“Sister, please...”

The silence stretched on into the night. Twilight watched Luna quietly as the dark alicorn's shoulders slowly slumped. She rose and approached the door, deciding that she might as well try.

“Princess?”

Nothing changed, and Twilight sagged, a happy little fantasy about her importance to Celestia punctured and deflating with a very sad wheeze in her heart. She opened her mouth again, but stopped short of saying anything more. Before she could button her trap back up and pretend like she wasn't going to do anything, though, she found Luna watching her. The moon princess' expectation was enough.

When Twilight spoke again, she could almost have been mistaken for Fluttershy, “Ce-- um,” she licked her lips nervously.

“Celly?”

The silence afterward was different--as if the stones of the castle themselves were appalled by Twilight's temerity. For a long moment, nothing continued to happen, as it had since they arrived. Just as Twilight began to droop and turn away from the door, there was an echoing CLICK, and the door swung open. There was enough tension in the air that, by all rights, the door should have creaked so loudly as to have been heard back in Ponyville, but the careful ministrations of the palace staff were too much; it opened noiselessly onto the dimly lit chamber.

The pair stepped gingerly into the room, side-by-side. Luna's eyes roved about, looking for anything out of place, but the room seemed to be as it always was—a place to store a bed, a brush, and a liquor cabinet. The fire was out, and Luna noticed the twinkle of shattered glass in the dead coals.

The sun princess herself was seated on the floor at the window with her back to them, a small pile of fine ashes—similar, perhaps, to the remains of papers blessed briefly by the full glory of the sun—making a neat cone next to her. As Luna approached, she caught sight of one yet-surviving sheet laying flat in front of her sister, blank, creamy and perfect save the blemish of one line.

Dear Twilight Sparkle

Ice water—no, dry ice—no, a... a helium slush, hit Luna right between wings and flowed straight down her spine. She pursed her lips, and they worked soundlessly for a brief moment. Her whole body settled with subtle determination, and she raised her chin

“We believe that the two of you have much to discuss. We are expected at night court.”

Luna turned to walk away, and Twilight looked back at her in shock. Her head swiveled to Celestia, who had folded her ears back and let her head sink between hunched shoulders in obvious shame. She settled on the paper for a moment, then returned to Luna, and she could feel her heart sinking into her stomach. What splashed back up was a dose of mad determination. Both princesses suddenly glowed in a violet magical field.

The alicorns were both too startled to slap Twilight's telekinesis aside, and the unicorn lifted them both into the air and set them down facing her at the other two points of a triangle. Then she picked Celestia back up and adjusted her slightly so that the triangle would be equilateral. Both goddesses were too busy staring at Twilight to comment.

With both princesses staring at her, Twilight's mad determination melted right back away.

“Um,”

They continued to stare expectantly, and Twilight sighed and hung her head.

“Princesses,” since she wasn't watching them, she missed the identically pained looks each alicorn briefly bore at the formality, “Please. Don't...” she hesitated again, then her head sunk a little lower, “I'm sorry. I'm damaging your friendship with each other, and it's been very selfish of me. I'll... I'll just go back to Ponyville,” her voice became very small, “I'm not worth you two fighting over.”

Twilight stood to leave; Celestia was the first to recover her voice.

“Twilight,” as always, it was enough to freeze the unicorn in her tracks. Celestia's voice was calm and soothing, though after so many years, it was possible she would have had to try to speak otherwise, “There is no fight, my... Twilight. I have seen the two of you at Luna's telescope, and... I certainly saw the two of you last night,” shame crept into her voice, “I took advantage of the both of you—I can scarcely believe how badly. You and Luna have a bright future together, and I look forward to watching you both,” Celestia flushed, “ah, metaphorically. From a distance.”

Luna was already shaking her head vehemently, “Nay, sister. My first memory upon... being cleansed is of the two of you in an embrace, reunited. You have constructed something very special that long predates my return to the worldly stage. It would be my eternal shame to lay a hoof upon it.”

Twilight leveled a glare of disbelief and irritation at the princesses, and she cut off Celestia's nascent rejoinder sharply, “Okay, what, so neither of you actually wants anything to do with me?”

The way both princesses' eyes flew open in horror was certainly gratifying, but they both immediately fell back to trying to leave Twilight in the others' hooves, and Twilight grew angrier and angrier with them both. She was all the way up to grinding her teeth and trying to glare a hole in the ceiling when a candle-flame suddenly lit itself in her mind. She stared between the princesses for a long moment—they didn't notice, they were both still trying to award Twilight to each other—and began to chuckle.

That shut them up quite quickly. But when they turned to stare at her, the matching miffed expressions only made Twilight break out into full laughter.

“Is there something amusing, Twilight?” The badly-masked irritation in Celestia's nearly sent Twilight into a fresh fit of giggles as she tried to calm down enough to explain herself.

“I just—hee! Whoo. Okay, wow,” Twilight stifled another giggle, then looked up at the princesses with a broad, impish smile, “Do you think,” she began, “Equestria has ever seen a trio of such horrible, inveterate martyrs?”

Both princesses stared at Twilight for a long, long moment, but Twilight kept grinning back up at them. Celestia was the first to crack a smile, but Luna was the first to let a chuckle escape. That set Twilight back off, and that set Celestia off entirely, and pretty soon they were all lying on the floor, laughing at themselves.

As they wiped the tears of laughter from their eyes, Twilight smiled fondly at the celestial sisters. She crossed over and sat herself down between them, and used her magic much more politely than before, gently nudging them both to come to her.

With an alicorn nestled up on either side of her, Twilight radiated an almost unbearable smug contentment. Still... a stray thought from earlier in the day flitted back across her mind, furrowing her brow slightly and spoiling her beatific smile. She shooed the thought away and tried to return to her new-found happy place, but a quiet interrogative noise put a stop to that—both goddesses had been too busy watching her fondly to miss the quick change of expression.

“Um,” Twilight flushed, and an unexpected timidness returned to her, certainly odd given what she'd just pulled with the two most powerful, most beautiful, et cetera mares in the world.

“Yes, Twilight?” Luna managed a quite passable imitation of her sister's teaching voice.

“Weeeell... you know. Most ponies and their sisters, they don't...” Twilight trailed off in embarrassment.

Luna blushed, “Oh. Ah. Yes... well, we were never...” Luna trailed off in turn, and Celestia picked up the thread, rubbing the back of her neck sheepishly with one hoof.

“Well, we're not actually sisters. In the, ah, strictly biological sense.”

“Oh,” Twilight blinked, nonplussed. That was... wow, actually pretty huge. She took a long moment to try and process that revelation, and reached one inescapable conclusion.

“...it's still really hot.”