"Well...it's certainly a unique home."
Celestia, as per usual, tried to maintain her famous air of regal calm and composure, but in a place such as this, even she was having a hard time with it. Discord's realm was awash with every single nonsense thing one could imagine, to the point where the idea of there being "laws of physics" had apparently just never occurred to the place. In the midst of all of it, the idea that his house itself would just be a simple cottage seemed, in all honesty, the strangest thing of all here. However, the Princess of the sun was here for a reason, and after taking a few calming breaths, she trotted right up to the front door, raising her hoof to give a gentle knock upon it. But it would appear as though her presence was already known, for before her hoof made contact, the door opened, revealing the smiling face of Discord beyond.
"Celestia! What a delight to see you here! And to think, I honestly thought you'd have trouble getting here!"
Celestia, in spite of the continuing oddness of her surroundings, offered a genuine smile to her colleague for the afternoon.
"Discord, thank you again for inviting me."
The spirit of chaos waved her off.
"Oh pish-posh! Think nothing of it! What's the point of being old friends if we can't take a moment to catch up every once in a while?"
Celestia giggled slightly, then watched as her Draconequus friend stepped aside.
"Welcome!" he greeted.
The Princess gave a slight bow of her head in that polite way of hers, but as she took her first step into her friend's home, her eyes widened. Despite the quaint and cosy exterior, the interior of the cottage was as wild and crazy as Discord himself, with a great many oddities and bizarre randomness happening every single moment. At a glance, it was the spitting image of Fluttershy's home, albeit filled to the brim with things that the animal lover wouldn't ever have herself. Discord, waltzing right on in, chose a chair for himself and sat upon the top of it. Not in the chair, I repeat, but on top. Celestia blinked, then smiled again.
"Well, I see my expectations have been met and surpassed."
Discord, clicking his fingers to summon a tray of tea, chuckled heartily.
"I aim to please, Celestia."
Taking a seat herself, the mare accepted one of the offered cups, and while Discord struggled to keep his currently-floating tea actually in its cup, Celestia merely sipped hers calmly.
"So, I trust you've been keeping well? I must admit, your invitation was somewhat unexpected."
Discord smiled back to her.
"Oh, I've been wonderful, Tia! Why, only yesterday I decided to see what it would be like to have a T-Rex for a pet!"
He shuddered.
"It...didn't quite work out for me."
Celestia giggled again.
"Oh my! But, then again, pets are a great responsibility."
Discord raised his cup
"One I fully intend to avoid for the time being."
With that, he took a hearty slurp, downing his tea in one fell swoop. Celestia, by contrast, was continuing to sip hers, bit by bit, in a far slower pace, allowing her to take in the bizarre home of her friend.
"If I may ask, what do you do when you're all alone here? I imagine a Lord of Chaos can keep himself rather occupied?"
Discord's chest puffed up with pride.
"Oh, indeed! Why, there's so many things to do! For instance..."
He snapped his fingers, conjuring a baseball into his claws, before promptly throwing it upwards, right into the upside-down volcano that resided on his ceiling, which Celestia only now realised was there. Discord then raised three fingers, counting down. Three, two, one. Then, the volcano erupted a barrage, not of lava, but of confetti, eliciting a guffaw from the Draconequus.
"Haha! Gets me every time!"
Celestia nodded, maintaining her smile.
"Quite! I would imagine Pinkie would appreciate that also."
Discord tapped his chin, pondering that,
"Oh! Good point!"
He snapped his fingers again, bringing forth a paper pad, and after transforming one of his own fingers into a pen, he started to scribble on it.
"Not to self...invite Pinkie."
Another snap, and both the paper and pen-finger disappeared. With "normality" resumed, Discord again gulped some more tea.
"Oh, it truly is nice to have someone else around to visit. Fluttershy's was wonderful, but I felt it was high time I brought over the pony I've known longest."
Celestia raised her cup slightly.
"And I appreciate it."
Discord sighed, finally slipping into his chair properly, reclining against its back and looking more than comfortable.
"Oh, the things we could do and talk about, Tia. The things we could see!"
Celestia nodded, taking another sip before commenting on that.
"Indeed. Your realm has quite the collection of strange and wonderful sights I noticed."
But Discord rolled his eyes.
"Believe me, we don't need to go out there for something entertaining! Why..."
He looked down to the floor.
"...we can find our fun right here!"
At first, Celestia was unsure of what Discord was talking about, but then, as he caused his chair to hover slightly closer to her, he looked down to the floor again. Celestia too looked down there, and paid attention for the first time to the swirling purple vortex that lay there. Like everything else here, she'd tried to take it in stride, never commenting on it, but now it appeared as though Discord had some plan in mind for it. With a snap of his fingers, the chaos-spirit caused the vortex to convulse, shifting and twirling until, to Celestia's surprise, she started to see images in it. Places she knew, like Canterlot, but which somehow looked different to how she remembered.
"What is this?" she reasonably asked.
Discord smirked.
"Oh, it is a wondrous thing, my friend. With a mere snap, this little pool can grant us sights of both this world..."
His smirk deepened.
"...and others."
Celestia looked to him with confusion, prompting Discord to snap once more. Now, the vortex changed again, and the image that appeared was something that caused a grimace on Celestia's face. It was an all-too familiar sight, her land, Equestria, but under the complete control of Discord. It was far too much like their ancient conflict for her liking, but then she noticed, to her shock, that she saw herself within the image. And not only her, but Luna as well, dressed utterly ridiculously and being chased around by a victorious-looking Discord. As for the Discord beside her, he was rather tickled by the sight.
"Why hello there, King Discord!" he declared with a wave.
The one in the other world had apparently heard him, and stopped to look upwards, through the vortex, with a somewhat uninterested look.
"Oh, hello there, much-less-interesting Discord."
The present Discord frowned, giving a quick "hmph" before giving another snap, causing the image to disappear.
"Well, I know somebody who's getting unfriended today!"
Celestia, who was understandably taken aback by all this, looked to her tea-partner.
"And...you can gaze upon any reality? Any world?"
Discord regained his earlier smile.
"Oh, certainly!"
He grinned mischievously.
"Shall we entertain ourselves by...taking a peek here and there?"
Celestia looked to him, aghast and looking more than a little indignant.
"Discord! Are you suggesting that we use your chaotic powers to spy on the private lives of those from other worlds for our own amusement?!"
Discord gave a quick shrug, trying to look as innocent as possible, and as he did this, Celestia pondered the proposal, before finally looking to him with a slight smirk of her own.
"...What exactly did you have in mind?"
Chuckling, Discord gave a slight bow to her, before promptly raising is hand.
"Let's check out the menu, shall we?"
Another snap, and this time the image changed to one that was wholly unfamiliar to Celestia's eyes. It appeared to be a school of some sort, but the beings going in and out of it were not ponies by any stretch of the imagination. They looked like upright-walking apes, all fully clothed and looking about as odd as anything Celestia had ever seen. But, before she had a chance to ask about all of this, she noticed one of them in particular. A female by the looks of it, who bore a hairstyle that was quite familiar to the immortal Princess.
"...Sunset Shimmer?"
Realisation came to her, and a smile returned to her lips.
"Ah, yes...this is the world beyond the mirror. The one Twilight has often spoken to me about. I have never seen it with my own eyes before."
She looked to the image with softness and warmth, seeing Sunset smiling at her school.
"I am glad my old student is happy there."
Then, the moment was interrupted when, to Celestia's slight annoyance, Discord began to snicker under his breath, covering his mouth but still letting the sounds of his laughter leak through. Celestia, looking to him, raised an eyebrow.
"Something funny?"
But Discord merely shook his head, bringing out a fake halo atop his head as he spoke.
"Oh, don't mind me. Just silly Discord being silly."
Celestia knew he was up to something, but said nothing, instead watching as the Draconequus began to look to the vortex himself.
"I was just enjoying the sight of all those eager young students getting ready to start the new school day. Like Sunset..."
He pointed to the girl in the image.
"...and Twilight..."
Likewise, he now pointed to what Celestia too noticed was a purple-haired young lady, just in time for her to not notice Discord smirking as he finished speaking.
"...and Spike."
Celestia looked on, ready to see an excited puppy enter the vision she was seeing. Instead, and to her great confusion, a young male human came. From what little Celestia knew of humans, he appeared to be several years younger than Twilight or Sunset, and bore distinct purple skin and a somewhat messy-looking green head of hair, clearly marking him as Spike. But still, the fact that he was not canine right now is what truly took her off-guard.
"But...Twilight told me the Spike of that realm was..."
Then, ever so slowly, Celestia was once more struck with a bout of realisation. Closing her eyes, she sighed, then re-opened them with a slight nod of her head.
"...This is not the world on the other side of the mirror, is it, Discord?"
Discord, stroking his beard, considered that.
"Weeeeeeeell...yes and no. It is...just not the one you've been told of."
Again, Celestia nodded.
"An alternate human reality. One different from the one Twilight spoke of."
Then, a new thought came to her, and her shoulders slumped slightly.
"That...is not my Sunset Shimmer, is it?"
Discord shook his head.
"No. In fact, that world has no connection to ours whatsoever. No portals connecting us, no students who are secretly from Equestria...and no magic."
Celestia mused on that notion.
"A human realm...completely divorced from any Equestrian influence. Fascinating."
Discord scratched his head.
"Well, aside from the fact that we're watching it of course."
That notion suddenly reminded Celestia of what the two of them were doing, and she tapped her own chin.
"I suppose...it would be interesting, seeing what differences there are."
Discord nodded in agreement.
"Oh, certainly! And who knows? Just because there's no magic there doesn't mean there can't still be fun for them...right? You know how crazy High School can get!"
Celestia's face was, as usual, hard to read, but Discord eagerly watched her as she thought the whole matter over. With grace and care, she once more picked up her tea-cup, giving it a quick sip as she left her Draconequus friend waiting. She took silent amusement in drawing the moment out, but at long last, she looked to her colleague with a knowing smile.
"So...how will this day go for them, I wonder?"