Lily loved to swim.
She always had, really. She'd loved it! It didn't matter where. She'd swam in the ocean, in lakes, in rivers, and all manner of pools. She was a part of her high school's swim team. There was just something about being in the water that Lily loved. She'd trained herself to be able to hold her breath for longer and longer amounts of time, and had been steadily building up her speed.
It was thanks to Lily that her school had earned several trophies - and she had a whole shelf of them at home dedicated to various competitions she'd been a part of. But the competition aspect wasn't why she was interested. It was more or less just a byproduct of the fact that she loved to swim - and that being on the team meant she got to do more of it. And if it helped her get into a good college down the line, well, so much the better, right?
It was after her classes, and she was doing laps in the pool before heading home. The seventeen year old sliced through the water, powerful arms and legs propelling her forward.
Two of her friends, Daisy and Jackie, were sitting on the sidelines, talking to themselves while Lily swam.
The day before, she'd gone swimming in the ocean, though it had been kind of weird. While she was out in the waves, she'd gotten a bit turned around at one point, and it felt like...she'd swam through something, maybe? Whatever it was, it had been odd, and had left her feeling odd for the rest of the evening.
Either way, Lily was relieved that she felt better today.
Actually, that wasn't true - she didn't just feel better, she felt great. It felt like she was swimming faster than she had before, and with hardly as much effort as usual.
She pulled up at the edge of the pool, taking a break as she gazed over at her friends.
"Damn girl!" Jackie called. "Are you part fish or something? You're moving great!"
Lily shot her friend a wide smile. "Thanks," she said. "Just in the groove I guess."
"You keep that up, we're gonna bring home another championship win," Daisy said, who was also on the swim team.
"Hell yeah!" Lily said, laughing and turning over in the pool. Another few laps and she'd be ready to call it a day.
She took off once more, gliding through the water...
Except...
Something was off.
Lily jerked in surprise, her movement thrown off - her legs - something was wrong with her legs!
She twisted around underwater, trying to look back - her legs! There was something - something was on them! Some kind of rash, maybe?? She couldn't really see properly. She tried to twist back around to get back up - but - her legs weren't moving properly now! They felt weak of a sudden, not really obeying her commands properly. She began to twist and turn, waving her arms, trying to return to the surface. Her lungs were beginning to burn now - normally she could hold her breath for a long time, but that was generally during moments where she wasn't about to lose her shit.
And then there was a sudden reverberation and the body of Daisy entered the pool. Daisy swiftly swam over to her, and a moment later, strong arms grabbed around under her arms and began to hoist her up. Her head broke the surface a moment later, and she let out a shuddering gasp, gratefully taking in air.
"Lily!" Jackie screeched from the side.
"M-my legs!" Lily cried, coughing slightly.
Daisy swam them over to the edge, and she and Jackie were able to drag Lily's body from the pool.
She lay prone on the floor, coughing. Daisy dragged herself up and looked down at Lily with wide eyes.
"Lily! Lily, are you okay?? What happened?!"
"My legs..." Lily moaned. Even though she was out of the water, the strange sensation was getting stronger. It almost felt like her legs had gone completely numb.
"Holy shit!" Jackie gasped.
Lily managed to bring herself up a bit and look down, where she let out a horrified gasp.
Her legs!
They looked...awful! They were covered in some kind of blue...rash? Dead skin?? She couldn't tell - whatever it was, it was slimy looking, and very gross, and seemed to be running down the entire length of her legs. Worse - it wasn't just running down her legs - it was coating her legs entirely - and it - shit, it was gluing them together! What the hell was this stuff? She could see the weird slimy material stretching between her legs, and she tried to pry them apart.
"What the hell...?!" she gasped. "N-no, what's...?!"
"What the fuck?" Daisy gasped, backing up a few steps.
"What's going on?! Omigod, I'm gonna be sick, what is that??" Jackie shouted.
Lily watched, horrified, as the weird material began to get thicker, and began to bind her legs together even more - she couldn't even see her toes anymore.
And then - right before her eyes - she watched as her feet began to flatten out. Her mouth dropped open in horror, and...
No. No. No that wasn't possible.
No no no.
No.
It wasn't - that wasn't - nope. That - that wasn't...
"Holy shit," Daisy breathed again.
"What the fuuuuck," Jackie gasped.
Lily was speechless - her feet...they had become a fin. Like...a full on fin. A slightly blue and purple translucent fin...
And the slimy material that had been covering her legs...there was no gap between her legs anymore. They had fully fused together. And she could no longer feel any hint of her legs at all anymore. They'd pressed together fully...the slimy, slightly shimmering material...
She put down a hand to feel it...there was a somewhat slimy texture to the material on her legs...
Which looked awfully like some kind of fish skin...
"No..." Lily whispered. "No, what...that's not..."
"Lily?!" Jackie screeched. "You...you're a mermaid!"
And there it was. The word Lily had refused to think of. The one she'd refused to speak herself.
But it was true.
Somehow, without any explanation, she'd turned into a fucking mermaid while swimming at her school pool.
"What...what...how did...?" she gasped. She could feel herself beginning to panic...at least, she thought it was panic. What if it was something worse?
What if she was no longer able to breathe air??
"People don't just...don't just turn into mermaids!" Daisy protested, despite the evidence before her.
"I...I..." Lily gasped. The world around her was beginning to look blurry.