It was around 7am when Twilight realized something was wrong.
The time itself wasn’t the problem, as she’d expected to pull an all-nighter on this. The shipment of the new books for the library had to be sorted, after all, and it was going to take a while no matter when she got it done. Why prolong it? She’d done all-nighters before, back when she was in school.
Of course, some of the books she’d received weren’t easily classified in one genre or another, and that just wouldn’t do! Golden Oaks Library prided itself on being organized, and every book must have its place. There was no telling whether or not Two Lovers in Luna’s Light was truly a romance or if it strayed more into a different category, and there was only one way to be able to check!
So she’d read them, just enough to get a feel for where each book belonged. This was a routine procedure, and the coffee had helped her to focus as she worked. It was slow progress, and around midnight even Spike had called it quits and gone to bed. (He was, after all, just a kid.)
There should have been just her and Spike in the library.
It was around 7am when Twilight saw something else.
She jumped where she sat, nearly spilling her fourth mug of lukewarm coffee as she squinted into the darkness where she’d seen movement. “Hello?” She croaked after a moment, before clearing her throat and trying again. “Who’s there?”
The library answered her with sullen silence and she lit her horn brighter, illuminating the stacks of sorted books around her. Where she’d seen something, there were only books, with little room for anypony to be able to stand.
Maybe one of Fluttershy’s critters had gotten into the library? She bit her lip and took another sip. The dark, once welcoming, suddenly felt as though it was pressing in on her.
Must’ve been a moth or something. Twilight glanced out the window and noted with relief the first rosy gradients of sunrise before returning to her book. The Call of the Ancient Ruins wasn’t going to define itself into a genre, and she was just getting to the good part.
Inky Stars looked down as the city of Quetzlcoatl stretched out beneath her wings. There was so much lost history waiting to be rediscovered, and if it weren’t for the phoenix’s shrill cry, she wouldn’t have known there was anything beyond that waterfall. Taking a deep breath, she-
The walls moved.
Twilight leapt to her hooves. The dregs of her coffee soaked into the carpet, dangerously close to a stack of books, but she could hardly bring herself to care. The walls themselves had moved. She’d seen it. Out of the corners of her eyes, yes, but they’d still moved.
Or… or had they?
She rubbed her hoof against them blearily and tried to focus. That didn’t make sense. While the library was a tree, and was technically alive and therefore had to be pruned every once in a while, it never grew so fast that the change was visible. Maybe it was whichever animal had gotten inside that she’d seen earlier.
Her vision swam slightly as she watched the grain of wood. It seemed to pulse slightly, wavering back and forth the longer she squinted at it. Was it an illusion of sorts? She’d never noticed it doing that, but it was a magic tree and perhaps she’d never paid close enough attention, and-
There! Across the library, between the stacks, it happened again! It was as though the walls were getting closer, like they were inching in on her, and- no, no, that didn’t make any logical sense either. She marched up to the offending wall, mentally counting her steps. It was still the same size, even though she’d seen it move forward, had seen it shift out of the corners of her vision.
A chill crept up Twilight’s spine. The library was alive. It was magical. And it was moving, mostly when she wasn’t even looking at it. But the walls had moved inward, and she’d measured it (rudimentarily, but she considered herself an expert at knowing how much room she had to pace), and the space was still the same size, which meant…
Twilight frowned at her empty mug. She wanted something to drink, to help her work through this problem, and yet she hesitated to pick it up. A fresh pot of coffee could help her focus, but it also meant getting closer to the walls to re-light the stove.
She could do this, she just had to concentrate. If it’d moved inward and when she caught it, the library was at its usual size, then that must mean it had been at a larger size than usual when she hadn’t been watching it.
She sat down at the center of the library, as far as she could be from the towering slabs of wood. It’d been a bigger space when she wasn’t watching it, and it was a magical tree, and whenever she’d thought to check it, the space had always been exactly the same size, which meant it probably moved out and back in when she didn’t look, and if it happened more than once (as could be assumed, since she’d seen the walls shift more than once that night alone), then…
Twilight’s scream caught in her throat. The library was breathing.
Princesses above, perhaps the library was a creature, maybe even a sapient one capable of thought. It could be friendly, right? Maybe their relationship as… as parasite-like creatures inside the library’s mighty lungs was a mutually-beneficial one?
Thoughts of anglerfish and trap-making spiders filled Twilight’s mind unbidden, and suddenly it was difficult to swallow. Maybe it wasn’t the sort of relationship where both organisms won. Maybe the library was a predator…
… and she and Spike were its prey! Oh, no, Spike! She had to wake him before anything worse happened. It must’ve been biding its time until she’d become unaware, and then it’d start making its move when both ponies were asleep!
Come to think of it, she’d never really asked what happened to the librarian that had worked at Golden Oaks before she’d arrived. Were they about to meet the same fate that her predecessor had?
The walls closed in on her again, and that was all the answer she needed.
“SPIIIIIKE!” Twilight shrieked, bounding up the stairs as far away from the walls as she could. “Spike, we have to get out of here! Something really bad is going to happen!”
The bundle in the basket shifted and made an incoherent grumble. Twilight grit her teeth. Not good enough, they didn’t have enough time and she didn’t know how fast the library would react if it knew she was on to its malicious intent.
Her horn flared as she yanked the sleepy dragon out of his bed, dumping him on her back before she froze, eyes darting right and left. It’d moved again, she was sure of it. Was it her magic? Magical tree, responding to magic, closing in on magical prey- they had to get out.
“Ughh… what’s going on?” Spike asked blearily, claws digging into her back as she lept towards the stairs. “Twilight? Are you okay?”
“The library’s alive, Spike! We’ve got to get out of here!” She took the stairs three at a time, teetering on the edge as she raced towards the door.
Spike frowned as he processed her words. “The library,” he concluded in between steps, “is a tree.”
“I know that, Spike, but it’s a magical tree! It could be an entirely different species, and it’s moving! It’s moving inward, and it’ll do to us what it did to the last librarian!” She raced among the stacks of sorted books, knocking a few over without so much as a glance.
The dragon managed a tired “What?” before she flung them both through the front door of the library.
Panting, Twilight picked herself out of the dirt and turned around. The library stood against the salmon hues of morning, looking much like it always had, feigning innocence.
“Uhh, Twilight? What’s going on?” Spike tugged at her tail, snapping her out of her focused calculations for a brief annoying moment.
“The library, Spike. It’s a predator. It was going to eat us, and I saw the walls move! It was breathing, and I don’t know what it would’ve done if we stayed in there another minute!” She felt weak, her hooves wobbling with dizziness. Had it been draining her magic, or something even more sinister?
“The… library,” he echoed wearily behind her, and she nodded, mentally running through her options as she stared at it. She’d have to stop it from trying to consume any other ponies. It was still partially a tree, right? Would a giant axe work?
“I’ve got to destroy it,” she said, and she could hear the finality of that statement. A librarian forced to put an end to her own library. Maybe it was like an angler fish, and the books had been its lure.
“What?” Spike sounded far more awake than he had a few moments ago. “The library? Twilight, you can’t, you wouldn’t destroy a library, that’s just- you’re not thinking straight-”
“Fire!” She grinned and used a burst from her horn to swing open the door from a safe distance away. The heap of partially organized books could just barely be seen in the pale light of morning. Perfect. “Fire would kill most creatures, don’t you think? Well, except for dragons, but any other magical beast wouldn’t be able to live very long if there were flames in its lungs!”
“NO!”
She had hardly felt his feet as he vaulted off her back, but she could hear the echo of discharged magic in her skull as his front claws wrapped around her horn in the split second when she cast the fire spell.
Dirt. She tasted dirt, and something worse besides that. Tasted like an experiment gone wrong. Twilight lifted her head, then winced. Her ears were ringing, and that distracted her enough to keep her from noticing the concerned murmurs of the pony next to her.
“Darling? Oh, thank heavens you’re awake.” A white blur stepped in front of her vision. It leaned down, and purple ringlets framed the unfocused face of a very worried-looking Rarity. “Spike told me what happened, and asked if I could look after you whilst you recover. Spell interruption is uncomfortable at the best of times, and at the worst? Well, it’s never a pretty feeling.”
“What- the tree-” Twilight tried to stand, but her body refused to obey.
“Twilight, dear, the tree is fine. The books are fine. But you? You need to rest. You can sleep here, away from the library, but after you wake I’d love to discuss why one shouldn’t keep themselves going with caffeine and minimal rest. Trust me,” and there was a lighthearted laugh that brought a weak smile to Twilight’s muzzle as she felt herself slowly drift out of consciousness. “I’ve been there.”
“Spike?” She managed to mumble as her eyes slid shut of their own accord. She was safe here, with Rarity. The library… she’d deal with it when she woke up.
A hoof gently rubbed her mane. “He had quite a scare, but he will be alright. You, on the other hoof… I’m quite eager to know why you thought burning down the library was the only option left! But until you wake, darling, I’ll make sure nothing disturbs you.”
The sound faded, even the ringing in her ears, and Twilight felt herself succumb to a dreamless sleep.