Oh, hell yeah
I'm going to do the mermaid one: it sounds awesome, haha! Here it is:
Whatever the hell is rising from the fog rolling across the dark water, it's ugly.
Yosef clenches his teeth - the creature blinks, lids sliding vertically across bright yellow irises, ocean lapping around its rough, scaled hide. The creature stinks of salt and seaweed, and is covered in these slashes, deep and long, covering its body like snakes, and sweet god in heaven, they're gills.
Yosef is dead - this is the end, this monster from the depths of the sea will swallow him whole, consume his flesh, feast on his bones. It extends a webbed hand, covered in greenish muck, and smacks it wetly on the lip of his boat.
"Away, foul beast!" Yosef bursts, brandishing his broken oar. There's already too much water at his feet, and the hole in the wooden frame only invites more in.
Shall he drown, or be eaten?
The creature opens its mouth, rows or uneven, sharp teeth lined just beneath a pair of white, chapped lips.
Drown.
Definitely drown.
Yosef dives into the angry water on the other side of his rowboat. Brine stings his eyes, but he'd rather be lost to the depths of the sea and sleep forever in the arms of Poseidon than be torn apart by those horrid, nightmarish teeth...
Suddenly he's on a beach.
Yosef blinks.
The sun beats down, hot and tortuous, unforgiving, and his skin bakes in the heat. The moon is gone, the ocean a brilliant, gem blue, sparkling as crystal clear as glass. Somehow, it's daytime, but how is that possible?
His forehead smarts - he winces, gingerly touching the pads of his fingers to the sore spot. He must have hit his head on the bottom of the boat. But, how did he manage to wash ashore? The swells were dangerous, and there was no land in sight in the dark cover of night...
"You're welcome."
Yofes shrieks; the creature is lying beside him, bottom half long and slippery, covered in more greenish scales and ghastly grey flesh. He makes to jump to his feet, run away, but a pain in his leg brings him crashing back to the sand. The monster rolls its yellow eyes.
"You humans, so emotional," it drawls, and it begins to change.
It's sickly grey skin lightens, a pink hue rising as the sharp angles of its cheeks round out and smooth. The large, gruesome eyes shrink and slant inward, darkening to a compelling, rocky brown. Silken, thick hair grows from the bald scalp, pooling over the creature's hips, and it's torso-
"Goodness me!" Yosef exclaims, hastily covering his eyes as it takes the shape of a woman.
Totally topless.
Father Matteo would have his head for this.
It snorts, only it's oddly delicate, and the voice is no longer guttural and grotesque, but feminine and soft. "Is this better? I think your kind looks disgusting, but you poor air-breathers are beggars which cannot be choosers."
He peeks, hesitantly, from between his fingertips. "You're a...mermaid?"
She shrugs, and the transformation completes, leaving her quite stunning. The beast is no more. "If that's what you want to call me."
"Did you - did you bring me to shore?" Yosef asks.
"That awful excuse for a boat was sinking fast. I was going to tug it to land, but you had the bright idea to jump out and crack open your skull on the wood." The mermaid shakes her head. "Genius."
"Thank you, madam," he offers reverently, averting his eyes once again.
The mermaid watches him for several moments, brown eyes curious, and points a webbed finger towards the tall cliffs at the top of the beach. "A human settlement is beyond those rocks. You should find someone to splint your leg if you can make it to them. The fishermen come down often enough that you won't need to wait long."
And with that, she changes again, skin bubbling and shrinking and expending until the ugly monster is back, and she flashes him a toothy grin. Yosef screams.
"See you in the water, baby," she grouses, and leaps back into the froth of the waves.
A bit of an abrupt end, but that's how it goes with oneshots. I'm excited to see this thread get bigger! This is such a fun idea!