She insisted I put on a sweater before I headed out. When I asked why, she claimed it would complement my, and I quote, 'incredibly well proportioned rear end.' And then she started spouting erotic poetry until I complied.
I put this down to make it clear: There is no length she won't go to when pursuing a goal, and she'll pursue any goal that amuses her. Especially if it irritates me.
So, there I was, walking into Canterlot Palace. I claimed I was there to see Lemon Hearts, a friend of mine. My new companion amused herself by phasing her limbs in and out of the oblivious guards' helmets and loudly claiming she could read their thoughts. Soon enough, though, we were trotting down the palace halls.
"You have any idea where you're going?"
I rolled my eyes. "Of course I do. There are palace maps available whenever they host some big event, so the guests don't get lost. I've seen a pamphlet or two, and before you ask, yes, I do have a photographic memory."
"Okey doke! This should be easy peasy. Just don't look behind you and stop hunching your shoulders!" She backstroked in front of me. "If you don't want to look suspicious, don't act like you're sneaking around. You want ponies to think you belong here--you got hired recently, or something. Maybe let your eyes linger on some incredible piece of art before you 'catch yourself' and hurry along."
I gave her an annoyed look. "You know, for a hallucination, you're really good at thinking about this whole subterfuge thing."
"Well, I have to convince you I'm real. Part of the whole hallucinatory shindig right? That means acting chops. I'm just giving you some tips is all."
That got me to scoff. "What, do they have a school where they teach these things to mental projections?"
"...maaaaaaaaybe."
We walked and swam on in silence for a few seconds.
"...you know, if I'm seriously going to have to put up with you until I get some decent therapy, you're going to need a name," I pointed out. "I can't just keep mentally referring to you as 'crazy mirror pony.'"
"Crazy mirror pony?" She drew herself up, putting a hoof on her chest. "I much prefer 'Alternatively Intellectual Replicate,' thank you! But yeah, I should think up a pony name soon."
"'Pony name?' Do you already have, I don't know, a griffon name or something?"
For some reason that got her giggling again. "No, nono. Maybe. But probably no. But, hmm. Pony names. I look like you," she pointed out, swimming around my head. "So my name should too."
I stared at her, trying to comprehend that logic. "You want a name that sounds like Moondancer?"
"That looks like Moondancer," she clarified. "So that's Moon and Dancer. Mmm, not a lot I can do with Moon, that's pretty definitive. I'll go with Star, they're both in the night sky. Dancer, though, that's got a lot of potential...."
"Hmm." I nodded. "Waltz, ballet, tango, samba--"
"Spinner!" she shouted. "Because a lot of dances have spinning in them. Starspinner, got a nice ring to it."
I looked at her, my expression decidedly unimpressed. "Really. Starspinner. That's what you're going with."
"Or GlowrockRythymlord."
"...Starspinner it is," I sighed.
"WOOO!" The newly named Starspinner performed an odd little celebratory dance. "Pony name, get! Now, on to more important things, how far are we from Celestia's private chambers?"
"Down this hall, up two flights of stairs, and then we take a right and the third left. That will get us to the Solar tower."
"Solar tower? Huh." Starspinner tapped her chin. "Is there a Lunar tower?"
I rolled my eyes. "Yes, there's a Lunar tower."
"What's it used for?"
I opened my mouth... and paused. In all my memory, I had never heard of anything happening in the Lunar tower. It wasn't a servant's quarters, or an office for some politician, or even just a fancy place to throw a party. It... was just there, on the map, with all the pamphlets asking, politely, that nopony enter.
"I... don't actually know," I admitted, reluctantly. "Maybe it just fell out of use, for some reason."
"For some reason, she says." Starspinner got her look again, the 'messing with Moondancer' look. "Say, while we're here, why don't we go check it out?"
I frowned at her. "I thought you wanted me to poke around Celestia's private chambers."
"Meh, we can do that later. This is much more interesting." She kicked down and floated in front of me. "It's named after the moon, you've got a moon on your flank, there's the possibility that Celestia is hiding something really important in there... if we find nothing, we can just walk right on out. And if we do find something, well."
"...well what?"
"Well what indeed? Come'n, Moondancer, you can't not have the teensiest little smidgen of curiosity somewhere in that lovingly cluttered noggin of yours."
I glanced away, trying to think things through logically. Admittedly, I was going insane--or at least, believed I was going insane--which in all the books I had read tended to let ponies open themselves up to possibilities they would have otherwise automatically rejected. Furthermore, I was already in the palace, with the explicit intent of screwing with Celestia. Her own chambers might have been accessible, but now that I thought about it, the probability of them having an active guard presence even in her absence was high; the Lunar tower, though, was unlikely to be guarded beyond a simple pair of gate watchers, and if I was indeed going crazy I felt I could outmanuver a couple of guards far more easily than whoever was in Celestia's chambers.
"...fine. We'll head for the Lunar tower."
"YES!" Starspinner pumped her hoof. "Lead the way, filly!"
I had to roll my eyes at her eagerness. I assumed, ignorantly, that I was just projecting my own curiosity onto her and she, somehow, translated that into hyper-anticipation. Still, at least it provided her a distraction as she started humming some tune... that I had never heard before, so I thought she was making it up.
That really should have been my first warning, in retrospect, that Starspinner was no mere hallucination. But as it was, it wouldn't be until we arrived at the unguarded Lunar Tower that I began to suspect Starspinner had her own goals, goals which she was keeping hidden.
She floated up to the door, almost reverently, and smiled at the crescent symbol on it. "How much did ol' Tia put in here already? What has she got set up for you?"
I rose my eyebrow. "What are you talking about?"
Starspinner spun around, grinning broadly. "SPOILERS!" With that incredibly unhelpful proclamation, she kicked back through the door... and then stuck her head through it with that expression. "You coming in or what?"
"Fine, just give me a moment."
I leaned in, taking careful note of the lock and handles on the door. There didn't... seem to be any enchantments on it, aside from the lock being particularly sturdy. That in itself could have been a problem, as I had never really had a reason to look into lockpicking before. A quick push confirmed that yes, the door was indeed locked.
"...Welp. Can't get past this," I announced.
"Sure you can," Starspinner encouraged. "Just reach in the lock with your magic and rotate the drum while you push up each individual tumbler until you feel it give."
"....ahrk?!?!"
"What?" She shrugged. "I've... hmmm. I've read heist books, let's call it."
"I haven't!" I squeaked in protest.
"And I have, what's your point?"
"You are a figment of my imagination! You shouldn't know things I don't! That's," I gesticulated frantically, "that's a violation of the basic rules of psychology!"
"I cheat," she explained simply.
"That's not an explanation!"
"Look, Moondancer, I could explain how I know things. I really could. But you know something?" Starspinner pushed herself forward, floating in front of me. "I don't think you could handle it. Yet. Maybe later, after... things. Right now, though, you're going to have to accept that I am just a statistical anomaly, that happens to look like you."
I backed away slowly. "...you manipulated me."
"Mmmyeah. Not even going to deny that one."
"You, you... you planned this!"
"Actually no. I've been making this all up as I go."
"Why are you doing this to me?!" I cried. "What do you want?!"
Starspinner dragged a hoof down her face. "Oh geeze... look. You're the only pony that can see me, right? I don't know why that is, or why I got connected to you specifically. What I do know is that, basically, you're my only contact with the greater world. Which means, even if I only cared about you for my own purposes I would still have to try to care about you. And believe you me, I'm not nearly cold enough to see you as 'just' a tool. You are an incredible mare, or at least have the potential to be one, and if you have to be saddled with me for whatever reason, I just thought... well, I could help you, alright? I mean, when we first met you were on the first steps to a self-destructive spiral of isolation and depression. Not good. This?" She waved at the door. "This... is partially for my own amusement, not going to lie, but I honestly think this will be very good for you. When it happens."
I sat down, gaping at her. "You... you thought tricking me to raid Celestia's chambers would be good for me?"
"Actually I was going to trick you into waiting in her sister's chambers."
"She doesn't have a sister!"
Starspinner merely grinned, floating aside and waving a hoof at the door again.
"...that doesn't mean anything!" I protested. "And that's entirely besides the point anyway! I mean--what would me waiting in her sister's chambers even accomplish--how would this be a good thing for me?!"
"Weeeeeeell, I could tell you. But..." Starspinner leaned in. "Part of this is teaching you to think on your feet. Hooves. Whatever. Point is, I want you to be able to handle the unanticipated, unusual, and unnoticed. Your books are great... for preparation. You've got to learn how to apply what you've learned, though. Otherwise..." She smiled broadly. "Well. If we get caught up on what if, we won't get anywhere."
She swam through the door again, pausing halfway through. "So... are you going to stay out there, become part of the faceless masses, and disappear without any impact left on the world? Or are you going to pick that lock, open that door, and wait with me for a real adventure to start?"
That was a particularly... strange offer. I'd never heard anything like it, outside some novels, and I certainly never expected I would be the one to receive an offer like that. I mean, who was I? An ordinary pony...
...living in the capital city...
...with a high intelligence and great education...
...whose best friend had just been sent away by the princess.
Actually, in retrospect, I was something of a picture perfect 'thrown into a random situation' protagonist.
"...You're going to explain this eventually," I insisted, my horn lighting up as I focused on the lock. "And I mean everything, how you know things and what it is you're doing."
"...Fair enough. Ask me again after the youngest princess takes the throne."
I gave Starspinner a look, but she slipped through the door. And a few seconds later, the door swung open.