just beneath, sae x reader mermay fic
word count: 1158 words tags: implied yandere, mild coercion and manipulation, mild body horror/transformation ao3 link: here
mer!sae has a quiet fondness for the surface.
He romanticizes it, he’s aware. Sae is a thing that mirrors the world he comes from: cool, quiet, and still. He’s not made for the world above, and there are a few consequences when a creature of the below rises to the above.
The sun is hot. A concept he didn’t really think of until his scales had dried out and his skin had reddened and stung at the slightest touch. The world above was louder, too. Gulls squabbled back and forth as they drifted on air currents. The waves were louder, too. Thunderous against his eardrums when they crashed against sand and rock.
But, for reasons he can’t quite explain, he finds peace when he goes to the surface.
He knows he is an oddity, especially here. The gulls go silent for a breath, their white-and-gray bodies tilting so they can get a better view of him. Their yellow eyes are sharp, judging if he’s predator or prey; though both he and they know the distinction is always changing.
Some days, he is prey. Keeping just beneath the surface because the rocky beach is too loud, too crowded by two-legged bodies. Their splashing and laughter are too loud for him to come close. Humans have a familiarity in their faces and mannerisms, but are far too quick to take to excitement and fear for him to like.
This stretch of coast is mostly sheer bluffs, with a few rocky beaches dispersed by erosion or man. He skims them all, caught between boredom and curiosity. He had given up on there being something that would catch his attention.
Until you, of course.
Sae swims the length of the tiny, rocky beach that he’s stalked for the past week. Only the smallest and mundane of fish linger here now. A mer rarely takes territory, but when they do, it is usually because they are in love.
Sae fears the truth is much worse.
The sun dips toward the horizon, casting the sky and sea in an orange glow. He blinks water from his eyes when he breaks the surface, his gills gasping. Today, the gulls shriek to one another, wings flapping as they scatter to safer winds.
Tonight, Sae is a predator, though a gentle one. He tells himself that gentleness counts for something, that hunger wrapped in velvet is kinder than hunger bared.
The first time he saw you, you had come in the dark with a light in your hands. He watched you for nearly an hour, from his post on a rocky outcrop. You combed the beach, though, for what he did not think you knew. It wasn’t until you swung the light over him that he remembered he should have been more cautious. It wasn’t often he startled, and the splash of his exit had scared you so badly you had dropped the light and fled back over the hill to whatever was beyond it.
Yet, you had returned, just as he had, a few nights later.
He was more careful from then on. He had to be, for you glimpsed the thing you had been looking for. Some nights, you were a fevered thing, sweeping your light over the water. Other nights, you were still, standing at the edge where sea met land. Waiting, he imagined.
Tonight, you would have to do neither.
Sae swam to the shore for the first time in his life, stopping just short of beaching himself. You would come to him, he was certain.
There was a story he used to tell his little brother when they were both still small fry tucked into deep crevices for safety. About a mermaid who fell in love with a human and exchanged her tail for legs, only to suffer and then die because her human could not recognize her, let alone love her. Rin had a fascination with overcoming things — with winning, always — so Sae had to adjust the story’s original ending. Instead of the mermaid’s heartbreaking death, she slaughtered her beloved prince and his entire court before she perished.
Sae hadn’t been fond of either ending. Especially in light of his own predicament. The moral of the story, he had thought, was to scare young mers away from the surface and the dangers of humans. But that had been when he was young and feared losing his little brother.
Now, as the moon drapes the world in a gown of silver and he watches you come over the hill, steps hurried and nervous, he recognizes the flaw was not loving a human. No, love was never wrong. But that the mermaid left home.
As fond of the surface as Sae was, even he could recognize the dangers of it. It was too fast, too loud, too much. He could see it on you as you come to him. The shadows under your eyes, the tension you carried in your shoulders — even breathless with excitement and wonder as you step barefoot into the water to reach him, he sees how worn down you are.
He was careful with his begrudging request of the sea witch, to make sure you’d feel no pain. You will be scared at first, he knows, but not in pain. The ocean is so very big and looks so very empty. But you won’t be alone; he will stay with you, always.
Sae exhales softly, pushing water through his gills when you reach him. Saltwater laps at your collarbones, kisses the thin chain around your neck with the pink pearl pendant you had taken from him with shaking, cautious hands the night before. You’re so warm when you step close to him, pressing against his chest as his arms come around you.
He had worked for weeks to make you brave enough to agree to this. Sae had said he would show you the world below, he would give you a taste of what it was like to live as he did. Though… perhaps he had been careful to omit just how permanent the change would be.
He presses a kiss to your forehead — benediction or apology, even he isn’t sure. This will be the part he regrets the most, he thinks. The exposure of his half-truths.
For a heartbeat, he tastes your hesitation in the breath that fans across his face, bright as blood on his tongue. Then your lips find his. Magic answers as the contract is sealed. Your legs kick against him, and he holds you tighter. Water surges, opalescent, up your ribs; bone reshapes to cartilage, skin to scale. Panic bubbles from your throat; a wet, hiccupy sound that Sae swallows down.
Above, a lone gull calls once, then wheels away into the dark.
Sae exhales through his gills, cool and steady, while you struggle for a breath you no longer need. In time, you will forgive him. He will make sure of it.