Notes: De-anon from the kinkmeme. The prompt was: There are tales of beautiful women who are not human who are found by a humble peasant who manages to steal something of theirs and make them his wife.
In The Asian stories, it's the tales of the Celestial Maiden. In England and that area, it's the Selkies. And I'm quite sure there are more~
I want to see some story along those lines. Bonus asked for UKFemUS and a happy ending.

It had never been Arthur's intention to hurt her; looking back, he can't even say why he thought it would be a good idea to steal the selkie's pelt. That night, the Thunder Moon hung high in the dim sky, calling the selkie to the shore. Despite the warnings of his brothers, Arthur crept down to the jagged rocks of the coast and watched as the selkies' shed their fur coats to dance.

They were all graceful and long limbed, spinning and laughing, singing and dancing. He was so entranced that a careless misstep sent some loose rocks falling, clacking loudly all the way down.

The selkies heard. Most of them rushed to retrieve their furs and return to the sea, but a few braver ones stayed. The boldest of the remaining tiptoed over to his hiding place; he would have run then, if he hadn't been struck witless in terror. However, she didn't appear angry or vengeful. She peered over the rock he had hidden behind, examining him curiously. Then her grey blue eyes seemed to light up in the moonlight and she offered him her hand.

He didn't know why he accepted, but the next thing he knew, she was dragging him into the open, pulling insistently until they reached the rest of the group. Her sisters eyed him with more caution then she showed, but after she barked something to them they relaxed. They began to sway and sing once more while their more nervous sisters crept back to the beach.

His blue eyed selkie merely grinned at him and pulled him into a dance.

He lost track of time that night as he spun and jumped along with her. The more adventurous selkies even dragged him away to dance with them, but in the end, she caught his hand again. But instead of pulling him into another dance, she tugged him away from the other selkies.

There was no chance to ask what she was doing; the way she began to tug at his clothes was answer enough. He only glanced back once to the others—they were out in the open where any of her sisters could see—but then she nipped at his collarbone and he found that he just didn't give a damn.

When they finished, he tucked his head into the crook of her neck while she purred and tugged him closer. "Do you even have a name?" he asked, feeling sheepish as reality sunk in.

To his surprise, she answered. "I've never had a use for one. Why, would you like to give me one?" He stared for a moment, trying to think it over. She merely laughed and rolled him over so that she was on top. "You think about it," she murmured pressing a kiss to the tip of his nose as she rolled her hips against his to draw out a strangled moan, "after we're finished."

It was almost dawn when she finally fell asleep, curled up against his side. He watched as her sisters grabbed their pelts and returned to the sea. No matter how closely he watched, he couldn't pinpoint the moment when they went from beautiful women to slick seals slipping beneath the waves. More and more of her sisters vanished, the piles of pelts shrinking until there was only one unclaimed fur left.

It had to be hers; glancing to his side, he watched as she slept on, a small smile gracing her lips as she tucked herself closer to him. She was by far the most beautiful woman he'd ever met, but he had admired her gall when she climbed up to meet him while her sisters faltered, and he liked how sure and eager she was when she pulled him away from the dancing. She had wanted him; someone had wanted the unsightly runt of his family. Someone beautiful and brave chose him for once in his life, and it was enough to make his heart ache.

A plan—simple and astoundingly stupid—bloomed into his mind.

Slowly he peeled himself away from her, despite the intense urge to remain, and snuck over to the last fur. While she slept and her sisters swam away, he snatched the pelt and raced home.

Locking the hide in a chest, he hid the key on a leather thong and tucked it beneath his shirt. Now that all the evidence was out of sight, Arthur could almost imagine the entire night had been a dream. Actually, not almost—it did seem too fantastic to be real. He almost had himself convinced that he had merely had a very realistic dream. After a very late breakfast, he forced himself to return to the shore just to prove to himself that there really was no way that anything had happened there last night at all.

At first, he looked out at the empty beach while his stomach twisted itself into a knot. "Just a dream," he sighed, watching as the waves broke against the shore.

The waves were rough, crashing into the sand forcefully. The sound lulled him into an unhappy calm. His peace didn't last long, however; no sooner had started to turn back then did a head and shoulders pop up from the water. Arthur stared as the selkie tossed her hair free from her face, snapped something in her harsh tongue, and then shoved her head back beneath the water.

Dumbfounded, he wandered closer to the water, watching as she bobbed up once more. She appeared to be frantically searching for something. Beneath his shirt, the key pressed against his heart like an icicle.

"You're still here?" he asked, a hand flying up to rest against the key as she broke through the surface once more.

She paused and then whipped around, her eyes going wide. "Oh, it's you! You came back," she exclaimed before charging out of the water. For a moment, he was terrified that she knew about the stolen hide and was going to kill him. Instead she grabbed his arms and tugged anxiously on them. "Please, I need help—I can't find my fur."

"Your fur?"

"Yes, yes, my pelt," she explained, tugging on his sleeves again. "I can't return to my pod without it—please, help me find it."

He couldn't resist her stricken expression so he listlessly began to pick over the beach with her until the sun sank low on the horizon. She collapsed to her knees and stared out at the sea, her eyes wide and her hands trembling. She looked as though her heart was breaking before him; the key hung from his neck like a lead weight.

He sat beside her, hesitating for a moment before putting his arm around her. "You—you can home with me." She snapped her head to the side and gazed sharply at him. "We can look for your fur more tomorrow."

Finally she nodded and he led her to his home. She perked up enough to curiously ask him about what the objects—no matter how mundane—in his house were. She was especially intrigued by the chest to his horror, although she claimed it was only because it reminded her of treasure chests she and her sisters found at shipwrecks.

For a week, he helped her in the fruitless searching until he explained he had to return to his job. Still, she spent every day searching the shore—often he would find her there either searching or singing, trying to call out to her sisters.

It was at the end of the second week when he turned to her and said "Abigail."

"Huh?"

"A name for you… would you mind if I called you Abigail?"

For the first time since the Thunder Moon, she smiled.

Four years rolled by and Arthur was never happier. Abigail gave birth to a handsome child with her eyes and his eyebrows to her amusement. They named him Peter and Abigail took to motherhood well, caring and loving the child whole heartedly. Mother and son were never far apart; Peter clung to her skirts as she worked during the day and in the evenings she would take him to the seashore to teach him to dance and sing her songs. Arthur was happiest sitting there on the sand, watching as she took Peter's tiny hands in hers and taught him how to kick his stubby legs to her song before she would grin and tug him up from his seat to join in.

Only during the harsh stormy nights, despite the twin sources of heat of his wife and son pressed against him, did the key's icy presence remind him of his terrible selfishness. As he lay there, he would think back to how his Abby would always sigh longingly and gaze out to sea just before she would swing Peter up onto her hip and take his hand in hers. Four years had done nothing to ease her desperation; some nights he would find her at the shore, cajoling Peter to "help mummy look for her fur".

Those nights, Arthur would press a hand to the key and kiss her forehead like a failed apology. She would smile at him and pull him closer despite Peter's fussing. He would only find sleep then, even if it was restless and haunted.

Morning light would banish those doubts and regrets though, and his heart would always warm when he heard his beloved's voice and son's laughter as they played at the shore. Life, forgetting those dark nights, was warm and perfect.

That perfection came crashing down one night, however, when Arthur found Peter alone, crying in the surf. Arthur grabbed his child before the waves could sweep him away and tried to soothe him. In the end, Peter finally manages to choke out the story: Abigail had forced open the lock of the chest, searching in hopes for some cloth to make Peter a new shirt. She had found the pelt and stared at it in silence for what Peter claimed was ages before racing away from their home. Peter had no chance to catch up to her and by the time he reached the beach she was already gone.

Silently, Arthur picked up his son and carried him home, ignoring the child's sobs and protests, demanding his father go find his mother. That night Arthur tucked his son in beside him, listening dully as his son cried himself to sleep. Tears welled up in his own eyes and he copied his son, pulling him closer and pressing his face to his son's hair as he wept.

A week passed and Arthur spent most of it with Peter scouring the shore. It was stupid and useless, but he kept searching and praying as he looked over every rock. He was distantly aware that he doing the same as Abigail had done so long ago and he wondered if his search was just as futile.

In the end, he couldn't keep looking—as a fisherman, he needed to return to his boat. He left Peter with his sister-in-law and ignored Peter's curses and crying as he walked away.

Whatever favor he had with the sea before seemed to have left with his wife that day. Not long after the boat left did the sky turned dark. A squall blew up and waves began to crash against the boat. There was no hope to return to dock, so the fishermen buckled down and tried to wait out the storm. The storm continued to swell and to everyone's horror they began to take on water faster than they could pump out. As they scurried to save their ship, a wave crashed into their side and Arthur found himself flung out into the waves. He only managed a strangled scream before he crashed into the water.

The force was enough to knock the air from his lungs, and while he managed to kick his way to the surface, he felt the pull of waves drag him back under.

It felt like divine retribution. He had stolen a selkie's coat, seduced and ensnared her all while keeping his secret. He deserved this he decided as his vision started to grey. He felt a powerful tug, pulling him back to the surface, but he was so exhausted that the minute his head cleared the waves he let it lull backwards and fell asleep.

When he awoke next, he was aware of two things. One, his back and legs were cold and soaked but his front was warm. Two, his head was lying against something soft and firm, not sand but not a pillow either. His body ached and refused to move; even his eyelids felt weighted, so he laid there trying to recover.

As he awoke further, he realized that his head was in a lap. Someone must have fished him out of the water, but they hadn't bothered to carry him out of the waves. They lapped at his sides, heading towards his feet.

Something was missing, he realized a moment later. The ever present frigid key wasn't bearing down on his chest for once and he found that he breathed easier without it. Perhaps the worn strap had snapped and been washed away. It was a lovely thought, almost enough to make him smile.

Someone spoke.

Face twisting, he tried to open his eyes. They were gummy and heavy, falling shut mere seconds after he opened then. He grunted and felt a tug at his neck—the strap was still there. His mood soured.

The voice spoke again. "This is the key to the chest, isn't it?"

He grunted again, this time in confusion. Who was talking?

"I always wondered about this key—you never went anywhere without it. I should have guessed it went to the chest."

Finally he got his eyes to open long enough to see his savior. He saw familiar blue grey eyes and wavy curls like wheat framing a tanned face and smile sweet enough to break his heart. "Abby?"

"This is that key, isn't it?"

He let his eyes shut in shame. "Yes."

Her fingers brushed his cheeks. "Why did you steal my pelt, Arthur?"

Why had he stolen it? He hadn't been thinking when he took it and locked it away. All he remembered was looking down at the beautiful woman next to him, the one person to choose him, and wanting her to stay. "Didn't…"

"Didn't what?"

"…want you… to leave…"

She was silent for a long time as she carded her fingers through his hair. "You stole my pelt. You hid it from me for years, even after I married you, after I had our son. You lied to me. You kept me a prisoner here on land, even when you knew how badly I wished to return home. You lied."

A drop of salt water stung his lips, but it was too warm to be a drop of seawater. Tears stung his eyes as well. "Yes."

She petted his cheeks and brushed away the tears that wouldn't stop. He was so tired, weariness worked into his bones. He was too tired to feel shame anymore.

"Why? Why did you lie? Why keep the secret for so long?"

"You would leave. You did leave."

"You lied."

"Yes," he sighed. "I am… sorry."

"I'm not. Sorry. For leaving."

He tried not to sob. "You shouldn't be."

"Leaving?"

"Be sorry."

She was quiet for a long time and Arthur was too tired—and too scared—to break the silence. He wanted to curl up then, coil up against her side like the night they first danced together under the Thunder Moon. His fingers twitched at the thought of curling into her once more and brushed against something rough and warm. She had laid something on top of him, he realized, something to warm him.

After a moment, it struck him. Her hide. She had placed her pelt across him.

He thought for a moment that he would die, his heart ached so. Instead he sobbed. "Missed you. God, I've missed you, Abby."

She stroked his face again. "… I know. Go to sleep, Arthur. Go to sleep."

He tried to protest, but she only shushed him. She began to sing, not one of her old wild and merry tunes, but a soft lullaby that she had forced him to teach her so she could sing it to Peter as well.

When he awoke next, he found himself warm and clean, tucked into bed. Gazing up at the ceiling, he tried to recall ever dragging himself home. He wondered for a moment if he hadn't actually dreamed everything—if the last five years hadn't been some impossible dream. It seemed far more possible; a selkie for a loving wife? He sighed and rolled over.

Only to find Abigail staring back at him from across the bed. Between them, Peter was tucked against his mother's side, his back to her front while he had a fist full of Arthur's shirt. Arthur blinked slowly.

"You're awake," she murmured. "Took you long enough."

He couldn't speak.

"It's been two days—Meggy brought Peter back last night. He was happy to see me."

He only nodded.

She raised an eyebrow. "Apparently he was the only one happy to see me."

"You came back," he finally managed.

She smiled, soft and sweet and if Peter wasn't caught between them he might have crashed into her for a kiss. "Yes, I did," she answered then frowned, reaching out to brush his face. "Oh, Arthur—don't cry, love. I hate it when you do."

He couldn't help it—he hardly noticed at all. "You really came home?"

She gave a soft laugh. "Yes, sweetheart, I really came home. You could welcome me back, you know."

Peter complained as they woke him when Arthur pulled her close to hug her. He settled for grumbling about jerk fathers rudely waking him up when he saw how happy they looked. His mother merely laughed and pulled him into the embrace as well.