Once upon a time, there was a shark. As is the way with such creatures, she had no name, or at least not a name as we would recognize it. She knew who she was, and she was very aware of the ways in which she was different from the other creatures around her, but she did not attach labels to the world around her. Had she been able to speak in a language that we might understand, she would have said something like "I am myself, and that is not". To a shark, that is all that one needs to know about the nuances of identity.
This shark kept herself to herself, even moreso than other sharks. She prowled the ocean's depths not with a predatory or a driven gaze, but with a bored one. She avoided anything that she wasn't eating or about to eat, and was more likely to swim away than fight those who meant to intrude on her space. When the seaponies came for her and tried to saddle her, she did not tear at their limbs or try to lure them into letting their guard down, as many unruly sharks did, but instead swatted at them with her tail and swam away.
All around her, the world moved. Predators and prey danced their merry dances in the whirling waters, and the politics of the seaponies wound through all of this and tried to make use of every flashing fin. And through it all, the shark swam. Unswayed. Unbowed. Uninterested.
Loneliness is not a problem reserved for those who breathe air. Even in a world where you might travel a mile straight upwards as easily as you would a mile to the left or the right, one might grow tired of the reality they surround themselves with. A fish can come to see themselves as the only whale in a sea of krill as easily as a pony might think themselves the only clever one in a kingdom of idiots. The shark had become bored with life as it was, and craved something different.
The shark turned her gaze upwards, and she sought out the surface. She was unaware that it was seeking her out in turn.
Once upon a time, there was a unicorn. Her name was Vinyl Scratch, or perhaps it was DJ PON-3, or maybe Blue the Electric Symphony. She had as many names as most ponies had scuff marks on their hooves, and the name she thought of as her own changed as quickly as the wind. Change was not one of her names, but it may as well have been for how much it would have said about her in a single word.
She considered herself unpredictable. One moment, she might be performing a sold-out concert with an audience of millions, the next she could be rapping on the streets of some town she doesn't even know how she ended up in. Her voice could be anything from synthesized bleeps and bloops to a flawless Cloudsdale accent, and none could guess what it would be until she opened her mouth. Her music was as fluid and ever-changing as whitewater rapids in the middle of an earthquake, sometimes shifting from genre to genre in the space between two notes. The only thing one could say going into her gigs was that they had no idea what was going to happen.
Sometimes, Vinyl Scratch slept. Usually, she just blinked for however long she could. She liked to tell ponies she could teleport, but all she could really do was pass out on moving trains, usually before she found her seat. "If you want to keep ponies guessing," she had famously said, "you have to keep yourself guessing too". She usually had a plan when she got on the train, but she'd always have forgotten it by the time she got off. If she was lucky, part of it might come back in time for the next train. Vinyl Scratch planned and lived her life in fits and starts, but most of all in bursts.
It was fun. It was awesome. It was exhausting. And one day, she kept telling herself, it might be worth it.
That night, she stood shoulder-deep in the waters of Horseshoe Bay, her back to the setting sun and her eyes turned towards Griffonstone, that mysterious land across the sea. Her speaker system and turntables were set between her and the Celestial Sea, and a small herd of groupies waited on the shores behind her. Tonight, she would play a song, and the ocean would echo with her music. Perhaps the fish would dance as the ponies did.
The shark had known what music was. She had not known what music could be.
She had heard the harps and flutes of the seaponies, but all that they ever played was mournful songs of remembrance. They had war drums, but even those were slow and nearly silent. Until that night, all that the shark had known of music was quiet and lilting. Then all of a sudden, the ocean shook and echoed with a new music, a sound like a hundred thousand beating hearts swimming away in panic. Had she been the swearing sort, the shark might have sworn that she heard strains of whalesong within that music, and something like the crash of rocks from time to time.
The shark was intrigued, and so she swam up into the shallows. As she drew closer, the music became even louder, and the beat grew more intense. Part of her insisted that she was hearing the heartbeat of some strange new fish, but the shark knew better. There was nothing in all the ocean that could make music like this, and that was enough to make her want to know more.
At last, she saw it. There were strange shapes, like the buildings of the seaponies but with much harder lines, and they were shaking and pulsing with sounds and lights that she hadn't known were even possible. And leading them, egging them on like she was driving a chariot of sound and fury, was a most unusual creature.
Fish have very few words. When you cannot speak, there is only so much that you might wish to say. While fish have over a hundred thousand words for water, they have only one word for the surface of the ocean, and nothing to describe the creatures that live above it. So when the shark saw the pony, she did not know what manner of creature it was. She knew only that it had made the music.
For the shark, that was all she needed to know.
Vinyl Scratch let her head loll forward, panting openly as she came crashing down from the rush of that last track. She stared at the rippling water, for the first time able to see the notes of her music echoing and fading. It was an amazing sight, the sort that might inspire a poet to write a ballad that would take the rest of his life to complete, or move a godless pony to invent a religion. Vinyl's eyes followed the ripples, while her horn coaxed the machine into its next track. As the first notes began to ring out beneath the waves, Vinyl saw the shark.
The predictable response would have been to be afraid. Instead, Vinyl decided to be curious. She reached over and adjusted the volume, cranking it up to see if that would drive away the shark. But rather than swim away from the invasive noise, the shark stayed, and drew ever so slightly nearer. Vinyl caught a glimpse of the beast's eyes, and she grinned as she recognized the look she was getting.
One of the most familiar sights to any great performance artist is that of a child's face when they decide that they want to grow up to be the one on the stage. In the case of ponies, that sight is coupled with a magical flash of light and a permanent tattoo. Vinyl Scratch had long ago lost count of how many times she'd seen ponies get their cutie marks at her concerts, but one thing she never forgot was the look in their eyes right before it happened.
The shark's eyes gleamed with that same wonderment and innocent fascination, its lips parted with that same eager smile. Vinyl guided the music over to a different beat, and watched the shark sway and bob in time with her song. Almost without realizing, she transformed Melody Maker's Oh What a Circus into Tempo Rubato's Ode to the Maddening Deep note by note, samplings from the Philharmonic Orchestra slowly overriding the electric thrummings and thumpings, until at last she seemed more a conductor than a disc jockey.
The shark came closer, until its nose was bumping against her main speaker. Vinyl stared into the eyes of the huge fish, and put her hooves up on the turntable. The two of them were so close, now. They both loved the music they were hearing, and as far as Vinyl could tell, they had the same reasons. Looking into those eyes and feeling them look back at her, Vinyl couldn't think of any time she had felt more of a connection to a fan.
She had to try. She let go of her instruments, setting the track to a long loop. Her horn glowed with a spell, a teleport that she hoped she'd have the energy for, and she leaned over and kissed the shark.
There are few things more magical in the world of Equestria than a kiss. The Elements of Harmony might be able to seal away horrific monsters for thousands of years, but it is only such things as friendship and love that can transform those monsters into heroes. The knight who fights for the sake of his fair lady will beat the knight fighting for himself any day. Some of the most powerful feats of magic ever performed in Equestria's history have been because of a single, intense moment of love.
Had the kiss come from any other pony, the shark might have merely begun to speak, or understood what ponies were and how it might come to understand them. The DJ would have given up their promising career and built a shack on the coast, and waded into the ocean every night to sit and talk with the shark.
But the kiss came from Vinyl Scratch, the one pony so unpredictable that she sometimes forgot how to speak for several hours at a time. Faced with a passionate kiss from a pony like that, reality only had one direction to bend in.
The shark faded beneath Vinyl's lips, as though it were a candle flickering out. But before she had time to shed a tear, something flickered back into reality. Something with the same grey color, the same deeply passionate eyes, and the same eager smile, but completely different in every other way.
Where the shark had been, a pony now stared back at Vinyl. She stood a little taller in the water, and a little closer too. Where the shark had barely noticed the kiss, the pony returned it, and eagerly leaned into it.
They held that kiss for almost a whole minute. When they parted for breath, the shark-pony smiled, and laughed as air filled her lungs for the first time in her life. Once she stopped giggling, Vinyl smiled and stroked her face with a hoof.
"Hi," she said, not quite sure how to greet a fish-turned-quadruped. "My name is Vinyl Scratch. But you, ah, you can just call me Vinyl."
The shark-pony tilted her head, staring at Vinyl's lips as though hypnotized. "Vvvvv..." Her face scrunched up, and she tried to stare at her own muzzle. As far as Vinyl could tell, the new pony was confused by her tongue's attempt to form words.
"Don't worry about that. We can figure that out later." Vinyl hugged the new pony, and grinned as the gesture was returned. "If I had to guess, I'd say things just got a lot more interesting."