Twilight Sparkle awoke with a start. Today was the day! She was getting married!
She had been waiting for this day for 12,573,669,001 years and 56 days. That was Equestrian days of course. Though Equus's sun had swallowed up the planet about seventy-eight billion years ago (it seemed time these days was always being measured in billions), the length of that planet's cycles of rotation about itself and its sun remained a standard unit of measure for her, if only out of nostalgia. Those brief few billion years she had spent there had been some of the best of her life. Speaking of the best years of her life, Twilight had a wedding to get ready for.
She trotted over to her dresser, floating in the blackness of space, where she had an assortment of clothing woven out of some of the last stardust left. There in the corner, sitting on a mannequine, was her beautiful off-white galaxy gown. It was stitched from the softest celestial silk, a labor of love now shimmering in her radiant presence like the natural stars once did. Her wedding dress was lovely. Rarity would have loved it, darling.
Twilight magicked the piece off of the dress form and onto her own lithe form--”from one form to another” she thought, before realizing it wasn’t really clever. She had been talking to herself a lot lately. She should probably see a doctor about that. Unfortunately, Dr. Twilight Velvet Snickerdoodle Sparkle, M.D. was the only doctor in town. The good news was that she was covered on her medical insurance plan.
Twilight Sparkle clipped her crescent moon earrings in, an ear flicking angrily when she accidentally pricked it, and trotted through the interstellar vacuum to her study. She needed to do one last run through of the numbers, to make sure everything, absolutely everything worked out. She would never cook the books. Perish the thought!
It was very hard, being your own wedding planner. Even for a practiced accountant like Twilight, it could be difficult to stick to a budget. Like, she wanted to have a few celebratory supernovas, but all the stars had burned out billions of years ago. She looked into borrowing some from a neighboring universe, but the cost proved to be prohibitive. So those plans had to be scrapped. She ended up settling for a few black hole gamma-ray bursts. Sure, they were fatal to most life forms and outside the visible spectrum of those that could survive, but since she and Nothingness were the only ones left, it didn't really matter.
She scanned the guest list again. It was starting to look like nopony was going to show up. This bummed out Twilight a bit, but she understood. They simply had other obligations. The Great Olden Ones had moved on to seeding other universes. Celestia and Luna, the royal sisters, had ascended to a higher plane aeons ago. True, their essences occasionally popped by to chat, but Twilight suspected they would not be stopping by today (Which was alright with her, as it meant that there would actually be leftover cake for once.). Only a few billion years after the cosmic ascension, her sister-in-law Cadance had exploded in a fit of romantic passion. So she wouldn't be coming either. Discord starved to death a good fifteen billion years ago as the chaos of the universe slowly became lowly randomness. All the other ascended Alicorns were just dead from old age. And nopony did ever end up finding any other life in the universe. That was kind of a killjoy, or perhaps fortunate, if their former interdimensional trading partners were anything to go by. Regardless, it looked like it would just be Twilight and her groom today.
Well, she could invite Smarty Pants. Oh wait, he was in a black hole. That wouldn't do. Yep. No guests. This was not surprising, for this universe was dead. But Twilight had been faithful to the Nothingness that was left, because as long as some magic remained, it was still her domain.
Twilight left her apartment building and flapped her wings, propelling her toward her destination. Being the immaculate planner she was, she actually had plenty of time to get there; a few tens of thousands of years, in fact.
During the few million years that the brane humans came from and inhabited was close enough to that in which Equestria resided to interact with it, Twilight Sparkle had become an ordained minister in no less than 457 human religions, so she definitely had the authority to marry ponies. It might be a little awkward to marry yourself (no, not like that), but Twilight the Reverend, Twilight the Scholar, Twilight the Librarian, and Twilight the Princess of Magic were all legally distinct entities, precisely for these kinds of situations.
So it was without hesitation that she entered the chapel (dug out of the center of a dead neutron star) and cued the black holes to begin thrumming “Here Comes the Bride”, three octaves too low for anypony to hear. She trotted down the aisle of the empty church (Of Latter Day Magicians). The veil obscuring her view at last lifted, Twilight glanced at her husband.
Nothing was at the altar, waiting patiently, a true gentlestallion.
She reached the front of the room and cleared her throat. “Guests, today we are gathered together today in celebration of a very special marriage. I am proud to have known Twilight since she was a little foal. I have watched her grow into a proud mare, and I know she has many great things ahead of her. Marriage is about…” Reverend Sparkle had one last lecture, and she was going to make the most of it.
Twilight tuned out her yammering and instead thought about her future. She was very much looking forward to doing Nothing. Heh, she blushed at her pun. Then she looked across at her husband-to-be and blushed again. He looked so alluring in his black tux.
The Reverend Twilight Sparkle kept blabbering on, and Twilight the bride began to suspect she was going to go on forever, but eventually, like the universe, she came to an end. “...Miss Sparkle, are you listening?”
Twilight snapped out of her reverie. “Huh? Oh, yeah, I do!”
“Well then, Nothingness, you may now kiss the bride!”
At long last, Twilight Sparkle embraced the Nothingness, and they became one.
That night, on their honeymoon aboard a neutrino cruise, the two lovers consummated their marriage (in the dark, mind you). And that is how the universe ended, not with a whimper, but with a bang.