I don't own Sherlock, just the idea for the story.
And yeah, I stole the Salana Ehyun Hiasis from Free Willy, so I better say I don't own that either.
"John," Sherlock murmured sleepily. "John, will you tell me a story?"
It was always something different after a satisfying case. Sherlock would flop down in his chair, lazy and happily boneless, and it would be, "John, can we watch Lord of the Rings again?" or "John, can you make tea?" or "John, will you write the whole of your favourite poem down my left arm?" Each time, they'd done what Sherlock wanted to do. John popped in The Return of the King and settled down on the couch; John made tea exactly how Sherlock liked it; John wrote the entirety of "The Lady of Shalott" down Sherlock's left arm, using the internet for reference. Always these things would put Sherlock to sleep, but always, just before he did, he would open his eyes a sliver and look at John and with a soft smile that said everything in the world, and he would say, "Thank you." And that was why John didn't mind one whit.
"I don't know any stories."
"Don't be silly. Everyone knows stories."
"What kind of story?"
"A fairytale. Something that doesn't make sense."
John sighed, though of course he wasn't really exasperated at all. He handed Sherlock a cup of tea and settled himself on the far end of the couch, curling his legs beneath him like a child. "All right, then." He scrubbed a hand through his hair, thinking for a minute. Sherlock waited, the tilt of his eyebrow expectant.
John closed his eyes and shut out everything in his head, all of the noises, the gunshots, Sherlock, the crime scenes and the sick people and Harry—it all stopped, instantly. First thought that comes into your head, John thought to himself, and the image of a beach sprung to life. Grey around the edges, fuzzy, but in sharp relief right in the middle was a small girl, no more than nine or ten years old, dancing around in the sand, dark red braids flying out behind her.
"A long time ago," John started, feeling extremely silly, "The only thing in the whole wide world was a beach. It was a sandy type of beach, with lots of little pools in the sand where the starfish grew. There were so many colours of starfish, you wouldn't believe, colours that don't even exist anymore because people won't believe in them. The waves would come in and meet the shore, and the waves and the shore had a lot of fun together. And there was a girl who looked no more than nine or ten years old but was really much older, almost as old as the beach. And she would count the starfish and categorize them and give them names and funerals when they died, and when she wasn't tending to her starfish, she danced. Her feet dug lightly into the sand, breaking its form over and over and over (but the sand didn't really mind). Her hands would go up and reach for the clouds and the stars and the sun, and sometimes she thought she could touch them if she just grew a little more."
John had kept his eyes closed as he spoke, just letting the story come as it would, but he heard a small shuffling noise and stopped, his eyelids cracking open of their own volition. Sherlock had moved, was no longer sitting in his chair; he pushed himself up and half-walked, half-crawled over the coffee table to the couch, where he sat down right next to John and snuggled up to him, his dark head resting on John's shoulder.
Sherlock allowed a moment for John to recover before nudging him in the ribs. "So she danced," he said, very quietly, getting lost in his own imagination. "She was a fairy, of course, but not the kind you think of from Peter Pan. She was a real fairy. Real fairies had marks on their wrists, like a small rudimentary set of wings. They were all born with them." John picked up Sherlock's limp wrist and drew the wings on the inside of the thin white stretch of skin with the tip of his finger. "Just there. That's how you know it's a real fairy." He put Sherlock's arm down, but Sherlock was having none of that. He nudged closer, reaching up and taking a handful of John's jumper lightly in his fingers.
"Anyway, she was a good fairy, of course, but there are bad fairies, and one of them found her at night as she was giving a eulogy for her favourite starfish, a bright blue one she'd named Henry. She was crying, and when the bad fairy snuck up on her, she never noticed. He caught one of her tears in his net—that's how you catch a fairy—and she was trapped.
"The sky wasn't happy about its only friend being taken, so it opened up, and there was a giant storm, thunder rolling almost constantly over the waves, lightning electrifying everything. The bad fairy said, 'You have three minutes to tell me where your treasure is before I start hurting you.' The girl, being the spiteful, impulsive thing she was, spit in the bad fairy's face."
John felt rather than heard Sherlock snort and was instantly annoyed at how foolish he felt. "If you're just gonna laugh, then—"
"No, stop," Sherlock pleaded, pulling John back down from his half-standing position above the couch. "I'm sorry. It's really quite lovely. Do go on." His eyes were so forlorn that John relented, not without a sigh of resignation as Sherlock nuzzled in against his side once more.
"The bad fairy, of course, was not happy about this, but he admired the girl for her spite. So he changed tactics. 'Help me find your treasure,' he implored, 'and we can share it. We'll live like kings. You'll love it.'
'Can I take care of my starfish?' the girl asked.
'No.'
Of course, the girl had never really intended to leave the beach, so she said, 'I wouldn't tell you where my treasure was if you were the last fairy on earth!'
"Well, the bad fairy was so surprised and angered by this that his face turned black. His eyes burned red and orange, deep holes of fire in his face, and he wielded an axe and cut off the girl's feet." John couldn't be sure, but he thought he felt Sherlock's hand tighten in his jumper. He also could have sworn he heard a soft intake of breath, something close to a gasp. "And still the girl kept her mouth shut. It was only then that she remembered a story her aunt had told her, a long time ago, when the girl was barely old enough to know what stars were. 'Little dove,' she remembered her aunt whispering, 'if you ever need me, just say these three words: Salana Ehyun Hiasis. If you say those words, I can hear you, wherever you are, and I will come and save you.' 'Do you promise, Aunt?' the girl asked. 'Yes. I promise.'
"So the girl opened her eyes, very slowly, until they were almost wide enough to eclipse her whole face. She turned her gaze on the bad fairy that held her captive, meeting his fire-eyes with her own. 'Salana Ehyun Hiasis,' she said very clearly, and the bad fairy's face twisted up with agony. Seconds later, the bad fairy began to scream, and then his skin began to rip itself to pieces, strip by strip, until he was nothing but a bleeding, screaming mess on the sand. Then he exploded in a puff of silver stardust, and the girl's aunt stepped forward through the cloud, smiling radiantly.
"The girl was of course overjoyed to see her but was still very sad about her feet. So the aunt sewed her a single long fin and stapled it to the girl's torso so that she could be a mermaid and swim under the water with her best friends the starfish. And she did, and she was happy for the rest of her long, long life. The end."
"Mmm," Sherlock sighed contentedly. "That was abysmal."
"You said you wanted something that made no sense," John retorted defensively. He was about a second away from shoving Sherlock off and huffing away to bed, but Sherlock let go of his jumper, snaked his arms around John's torso, and hugged him tightly, his curls pressed against John's collarbone.
"Thank you," he murmured, his voice muffled slightly by John's chest. John eased into a small smile and rested his hand on top of Sherlock's curls.
"You're welcome, Sherlock. Go to sleep."
And he did.