I actually wrote this a while ago, so here you go. I didn't really bother to edit it, either.
Twilight Sparkle never thought that the time spell would have repercussions like this.
Well, of course she had expected some, but nothing like this. It was just so completely out of this world, so fictional, so unrealistic that she just couldn't bear it.
"Why hello there. I'm the Doctor."
Twilight Sparkle refused to believe that this was real. It couldn't be! It was just an old mare's tale, a story told to young fillies and colts when they were being tucked into bed!
No, there was simply no way that this was real. The Doctor couldn't be real, not him. There were stories about him, legends of the lonely god that traversed the sea of time and space, wandering and befriending many distant worlds only dreamed of by children and insane ponies, never staying in one place, always flitting free like a bird, only showing up in the direst of circumstances.
The Doctor, the pony that always ran, far away from burning worlds that cursed his name and shining utopias that praised his name alike.
Even the books, her source of infinite knowledge of the world, were confused. Was he the Oncoming Storm, the destroyer of world, the nameless creature that was impossible, or was he simply a clever fake?
He wasn't real. He couldn't be; the books had said so. No pony could meddle with time and space so freely.
And yet, he had pulled her out of the swirling vortex that had burned her retinas past her tightly closed eyelids, the one that had nearly killed her. How could he have survived it? She has thankful, but he was impossible.
Had she finally snapped? Was she already dead?
She knew he was impossible.
Yet here he was, in his green tie and brown coat in all his glory, the hourglass cutie mark dispelling any suspicions she previously had of him being some random idiot. He had to have been there, had to have known somehow. Cutie marks were impossible to fake, and a cutie mark for time? There was only one way that could possibly have happened. He was a…
But that was just fairy tales, the stuff of myths, right? There was no way—
"Twilight, you're going in circles again," she mentally scolded herself, "Pay attention to the facts so we can solve this mystery."
Yes, that was it. He was probably only dressing up. Had Nightmare Night come early?
No, there was still snow out. It couldn't have been later than February at the latest.
Maybe it was one of those cosplayers, one of those insane ponies that were obsessed with dressing up as fictional characters and pretending to be them.
Twilight had to admit that this was a very impressive costume. The wooden blue box was tall and impressive, the words "POLICE PUBLIC CALL BOX" proudly shining on it. Twilight had no idea what it meant, but she didn't care. Most cosplayers probably didn't know what they were saying, either.
"No, no, no! You can't be real!" She said, finally responding to his outstretched hoof. "BEGONE! Stay out of my life!" Twilight pushed his hoof away and limped away, turning her back on him.
And she couldn't help but feel like she had missed out on the adventure of a lifetime when she saw the hurt look on his face and how the blue box truly had vanished with a vworp, just like the legends had said.
And most of all, she couldn't forgive herself for leaving the pony of legends, his name both sung and cursed in far off worlds, alone, to run with only his blue box for company.