Ocean Treasure
Title: Ocean Treasure
Pairing: Sherlock Holmes/John Watson
Rating: Explicit
Tags: merlock, octoJohn, interspecies sex, AU – Fantasy, potentially a crackfic…you read and decide
Summary: OctoJohn has been trying everything he can think of to attract Merlock’s attention.

A/N: Written for venvephe’s prompt for the Come At Once Challenge: “Something borrowed, something blue.”

Obvious first thought was wedding…but I’ve just spent an indulgent weekend with my favourite fandom friend/author/everything at Hamilton Pool, and the environs have recalibrated my brain.

I did take some liberties with cephalopod and shark biology…but since this is fantasy, I hope you can forgive me.

--- ✩ ✩ ✩ ---
John is slowly losing his mind.

He has been scouring the reef for months, searching for something that will finally impress Sherlock. He’s tried dozens of pieces of unique sea glass, a variety of sparkling trinkets leftover from human shipwrecks, and fossils of both terrestrial and aquatic origins. Each has been cast aside with no more than a passing glance and a dismissive ‘Hmmm.”

Once, he’d found giant isopod (probably brought up and discarded by wasteful humans) that had drawn just over an iota of Sherlock’s attention. But after flipping the creature over several times and carelessly prodding the carapace, Sherlock had dropped it back onto the coral with a shrug. “Hardly unprecedented, John.”

How else was John to let Sherlock know of his interest besides presenting him with something to tantalize his curiosity? That was the method preferred by courting merpeople, who presented one another with gifts tailored to their beloved’s personality and habits.

John had been certain the isopod would do it, but apparently not.

Thus, frustrated, John had reverted to the courting behaviours of his own species.

Unfortunately, his colourations apparently weren’t unique enough to catch Sherlock’s eye. Rotating the frequency and variety had no effect, nor did his attempts to imitate patterns found around the reef. John had then thrown off pheromones (which he had suspected merpeople could not detect and all evidence thus far supported this) and even once flashed his largest sucker discs. That would have had the attention of any cephalopod in range, but Sherlock hadn’t even noticed.

And just yesterday, in a last-ditch effort, John had tried striking poses, as was the standard propositioning behaviour of his species. Instead of recognizing John’s interest, Sherlock had asked him if he was having a fit. John had quickly fabricated a story about sleeping in a tight spot and needing a stretch, then turned an unattractive shade of puce.

The only logical conclusion: Sherlock was uninterested in John.

After all, with all his observational powers (and his impressive catalogue of reef life), there was no way that Sherlock could not know the significance of John’s actions.

--- ✩ ✩ ✩ ---

Today finds John basking in the rays of summer sun coming from a hole in the top of a seaside cavern.

Sherlock is busy skirting around the edges, searching for some kind of elusive cave creature. A waterfall empties thunderously into the water above them, while the distorted shapes of swallows flick in and out of the cave’s mouth.

It is supremely idyllic and John is completely focused on enjoying the restfulness of the location.

He is not spending a single moment preoccupied with thinking about wooing Sherlock. No. Not at all.

Well, maybe just a bit.

A frustrated groan sounds from across the cave, accompanied by a sulky, “This place is so dull.”

John opens his eyes to find Sherlock flicking his blue-grey tail at a school of yellow-striped fish, which scatter in frantic distress. John feels sorry for the fish. With his shark’s tail and sharp, angular fins, Sherlock gives the appearance of a deadly hunter even at rest. Add to that his merspecies’ predisposition to pointed features and finely textured skin, and he is at once predatory and striking.

And just like the Lamnidae they had evolved alongside, Sherlock’s people possess the unpredictable temperament.

“We just got here. You can’t be annoyed already.” One of John’s arms twitches in irritation of its own volition.

Sherlock’s silver eyes cut to him and then roll back. “Your simplistic, micro-brain couldn’t possibly understand. With most of your neurons in your arms it is a wonder you can even manage speech.”

John just shrugs and goes back to floating his apparently useless arms into the light penetrating from above. The velvety carpet of a sea mat under his back is divine and he is not going to allow Sherlock to ruin this moment for him. “Well, I miraculously do manage daily life. Must have more neurons than you think.”

A derisive snort is Sherlock’s only retort.

John chooses to ignore him. Declarations of death-inducing ennui are an hourly occurrence for Sherlock. In fact, if John did finally manage to alert Sherlock to his desire to mate and they went through with it, Sherlock would probably complain about the experience the whole time.

That certainly puts a damper on his libido. “I thought you need to look at some kind of slime to confirm something or another.”

Sherlock gnashes his pointed teeth. “Molly said she found a new species of nudibranch here yesterday. I wanted to test the acid strength of its mucus compared to the other species on the reef.”

“Why? Looking to chemically burn someone in the near future?”

“Besides my brother, no.”

John lifts his head. “And how exactly were you planning to evaluate the acid strength?”

“I don’t know. Maybe recruit some sea cucumbers?” Sherlock turns away and resumes his search for the elusive nudibranch.

“You can’t just go around testing harmful chemicals on helpless organisms,” protests John, now propping himself up onto his forearms. “Come on, Sherlock, that’s just cruel.”

Sherlock waves a hand behind his body. “They possess superior healing rates. It would hardly be a serious detriment.”

“It’s the principle of the thing, Sherlock. Are you really so bored that you have to inflict pain on others to feel happy?”

Clearly spoiling for a fight, Sherlock swims over and pushes into John’s space.

“What’s the point to anything? I’ve seen everything in this reef. There’s nothing left to explore, nothing new. My brain is over cycling and I am sick of trying to invent things to do. And you, floating around after me like a greedy scale-eating piranha –”

“If I’m such a parasite, then why haven’t you driven me off, yet?” John bites out. “Would hardly be a moment’s work for someone as ‘brilliant’ as you.”

Sherlock’s indignant expression would be comical, if John were not feeling so incensed. “It’s not difficult to be brilliant when I am constantly surrounded by idiocy.”

“Is that so? Guess I should save you the trouble of dealing with my stupidity and remove myself.”

Before Sherlock can shoot another barb his way, John jets away toward the back of the cave.

--- ✩ ✩ ✩ ---

Once he has dropped behind a dark ridge covered in red seaweed that hides him from sight, he slows to a gradual crawl down the rock face, his arms gasping and releasing rocky footholds. His heart is pounding furiously (in anger or just humiliated disappointment?) and his arms eventually anchor themselves on the old coral with a tighter grip than necessary.

Sherlock’s insults don’t ordinarily bother him so much. Clearly John’s recent emotional investment has made him more sensitive. It’s not like he is in love with Sherlock; he’d be a lunatic to care for someone who so quite obviously considers him to be no better than a parasite.

He may not be on the same intellectual level as the merman, but he is not a sycophant. He’d thought them friends. He’d even grown to care for the gorgeous idiot. In fact, if he hadn’t become so emotionally-invested in Sherlock’s well-being he would have strangled him for his mouth a long time ago.

His arms contract around the coral, and a piece breaks off into one of the loops.

“John?” calls Sherlock from beyond the ridge.

Not particularly interested in spending time with Sherlock until both of them have cooled off, John retreats further into the darkness, stopping only once the light from above has dimmed to a mute cobalt. Sherlock might still be able to find him, but the gloom will make it much more difficult.

At least, that’s what John thinks until a sparkling glow surrounding his arms diverts his attention from above.

John watches, intrigued: anytime he agitates the water around him, a blue light is left in the wake of his arms. John reaches his hand out and tries to grab at the source, only to have his fingers catalyse another pulse of fluorescence.

The light is coming from...some kind of plankton?

John cups the translucent organisms in his hands and lifts them to his face. A gentle stream of water from his mouth sends a cascade of soft blue light through them.

“Amazing,” he breathes, lighting the creatures up again with the exhalation.

This time, Sherlock’s voice comes from directly above him. “John?”

John reluctantly releases his glowing friends and looks up to see Sherlock hovering a few metres away. The resentful feeling returns and he frowns. “What? Your genius suddenly not so impressive without an adoring audience?”

But Sherlock is looking beyond him, to the fading mass of blue light.

“Dinoflagellates,” Sherlock identifies, then scoffs, “Hardly the pinnacle of evolution.”

“No-” begins John, then stops, watching the disturbed water near Sherlock’s tail pulse blue, observing how it transforms his ordinarily matte scales luminous.

A ridiculous idea plants itself into his head, completely usurping the hurt and anger. Before he thinks better of it, John propels himself to Sherlock’s side, reaches up, and tousles his hair.

The mussed locks glow muted blue, illuminating Sherlock’s delicate features and surprised eyes. He looks otherworldly like that, an unholy wraith of the sea, and John has never seen him look more beautiful. It’s as if he has trapped the stars in his hair, and his eyes reflect silver, like the moon.

Amazed, John does it again and again and again, his fingers happily entrapped by Sherlock’s hair.

When Sherlock sighs, John abruptly realizes what he is doing and quickly removes his hands, horror and shame spiking through him in equal measures.

But Sherlock is faster and grabs his wrists before they can retreat completely back to the safety of his body.

“John, what are you doing?” he inquires, sounding confused and uncertain. The glow fades away.

John swallows and tries to think of a way to explain, to defend his actions, without telling Sherlock why they have left him so awed. “The light, when it was in your hair…it was beautiful, it, uh, made you look beautiful. Not that you don’t look attractive already…what I mean, that is to say – you are gorgeous without the lights, but even lovelier with,” he finishes lamely.

Sherlock’s eyes narrow and his head quirks to one side as he processes John’s words. Without the luminescence provided by the tiny plankton, John fights to see Sherlock’s reaction clearly. His nerves surge to a full-on gallop, and the instinctive urge to escape swells.

Sherlock surprises him completely. He drops his head and kisses John, releasing John’s hands so that his own can pull John’s waist to his. Sherlock’s lips aren’t as cold as he’d expected. They are plush, though, and John stops breathing for the entirety of the unexpectedly tender kiss.

“I’m sorry,” Sherlock murmurs as he pulls away, and for a moment, John thinks he is apologizing for the kiss, but it is followed it up with, “For taking you for granted and for not seeing the signs.”

“The signs?” John repeats, completely forgoing the first half of the apology for the potential of the second.

A rumbling chuckle rolls through Sherlock’s chest. “The gifts? Your colouring? The posturing?”

John’s heart leaps. “You knew?”

“Knew? Yes. Paid heed to? No.” Sherlock shrugs. “I never thought I would have that sort of attention pointed my way.”

John strokes a thumb along Sherlock’s cheekbone. “Well, you have my attention now. What do you plan to do with it?”

A wicked grin spreads from one corner of Sherlock’s mouth to another. “Oh, I’m sure I can think of something.”

--- ✩ ✩ ✩ ---

They snog for a bit in the dark (which is frankly fantastic), but Sherlock clearly has other ideas.

With a strong grasp, Sherlock pulls John tightly against his lean body and flicks his tail determinately, bringing them both up back into the sunlight. John watches the glowing plankton trailing behind Sherlock’s tail into the dark. There is something magical about the way the water around them glows a joyful blue, as if the ocean itself is celebrating the realization of their feelings.

Sherlock would probably think him silly, so he does not voice his romanticized thoughts aloud. Instead, he wraps half of his arms around Sherlock’s torso and rests his head on Sherlock’s shoulder. It feels so comfortable, so right.

They clear the seaweed-coated ridge and burst back into the sunlight and open water of the cave. Sherlock presses John into the rock shelf around where he was searching for the errant nudibranch.

John finds he likes the sensation of little points of pain generated by the rock biting into his soft skin. The hiss he emits in reaction encourages Sherlock, who leans forward and nibbles on his shoulder.

“You’ve been lusting after me for quite a while, John,” he purrs into John’s ear after progressing upward from his shoulder. “All those knick-knacks, all those attempts to attract my attention.”

John slides a pair of arms down Sherlock’s back, wrapping around his arse, while his hands stroke the prominent shoulder blades. Sherlock’s sharp teeth press more insistently into his skin in response.

“Ahh, oh, Spirits yes, Sherlock.”

Sherlock’s features have sharpened further, John notes, as he pulls back to consider him with gleaming eyes. “I am going to eat you alive.”

Lust burbles up within John. He can feel his chromatophores involuntarily flashing, producing colours and patterns in rapid succession. Sherlock smirks at him, obviously noticing his loss of control.

“I rather like that I can cause this reaction.”

John pulls a face. “Oi, don’t get too cocky, yeah?”

The rough texture of Sherlock’s tongue joins his teeth worrying away at John’s shoulder. It provokes another string of uncontrolled utterances, which John does not bother to stem. Sherlock shows his appreciation by switching shoulders and biting down fully this time.

“Oh!” John shouts, then adds in case Sherlock thinks he genuinely hurt him, “Do that again. Now.”

Sherlock repeats the motion, pushing John against the rock harder this time, so that his entire back lights up in pained pleasure. At the same time, he grasps John’s nearest arm and begins rubbing his thin fingertips along the edges of the suction cups. Pure pleasure sparks through John’s nervous system and his mouth falls open again.

John wants to luxuriate in these sensations forever, but he also wants Sherlock overwhelmed right along with him.

He reaches between their bodies with two unoccupied arms and seeks out Sherlock’s claspers. They are external, always on display, and John has lusted after them countless times in the last few months. Each arm wraps around one and carefully strokes downward once in tandem.

Sherlock goes rigid. John cautiously strokes again and Sherlock moans as he drops his forehead onto John’s chest.

“You like that?”

“Yes, so don’t you dare stop.”

Grinning smugly, John continues the motion. He also begins to slide the arms not currently occupied with stroking Sherlock’s claspers over the rest of Sherlock’s body, shivering as his sensitive discs are overloaded with sensory information.

Sherlock lifts his head and finds John’s mouth again, this time shoving his tongue in roughly and using it to stroke against John’s soft one. John matches his arm’s rhythm on Sherlock’s claspers with the thrusting of their tongues.

The sensations must grow to be too much, because Sherlock abruptly wrenches his mouth back and looks down at John, panting.

“Is that what you want to do to me? Except with these?” John lightly constricts his arms around Sherlock’s claspers as they stroke again.

Sherlock emits a sound that is part hiss and part growl.

John takes that to mean yes, and shifts his upper body so that just his shoulders are braced against the abrasive rock. Contracting his arms, he draws Sherlock toward him, until Sherlock’s claspers are at his entrance and the rest of Sherlock’s torso is engulfed in John’s actively-exploring arms.

The predatory intensity of Sherlock’s presence lightens momentarily as he says in a careful tone, “John, one is fine. I don’t expect –”

“I’m not some fragile mermaid, Sherlock. I can take both. I want to take both,” John assures.

Before Sherlock can say anything else, he unfurls the arms around Sherlock’s claspers until just the ends are wrapped around both bases. And then, eyes locked on Sherlock’s face, John guides them into his body.

Both of them release loud breaths at the sensory intensity of the coupling. John watches as his skin pulses the most vivid purple he has ever produced in his life. Sherlock follows the bands of cream cycling through the purple, his expression one of amazement.

The initial pressure quickly eases and John regains control over his chromatophores. With a nod from John, Sherlock experimentally thrusts, leaning forward to grip the rock above John for leverage. Pleasure once more skitters through John’s body and along his arms, and he wraps them tighter around Sherlock’s hips as they piston into him.

Sherlock’s voice is low and rich. “Look at you, fighting to pull all of me in you, whimpering whenever I pull out. So greedy.”

“Yes, please,” John begs, “don’t stop.”

“Don’t stop what?” teases Sherlock, his grin toothy.

John’s voice is embarrassingly breathless. “Fucking me. Keep fucking me.”

Sherlock’s hips surge forward again and again, and John bolsters Sherlock’s forward momentum with aid from his arms and bracing against the wall.

John wants to kiss Sherlock, but their positions make it difficult. He settles for reaching one arm up and at Sherlock’s assent, thrusting the tip of it into Sherlock’s mouth.

The combined sensations of being filled and filling pushes John’s orgasm to the cusp.

Slightly dazed, he watches his arm slide in and out of Sherlock’s mouth, groaning shamelessly when Sherlock licks the underside as it slips out.

“Sherlock, I’m gonna…” John warns.

Sherlock’s eyes half-close. “Good. I want you to.”

“Are you?”

Sherlock nods, then picks up speed, fucking John harder than ever. Grunts are now issuing from John’s open mouth on every thrust inward, followed by gasps whenever Sherlock tongues the tip of his arm.

Sensory overload happens faster than John wants, but the orgasm is full-body and unbelievably intense. His arms go temporarily limp, but he manages to recover enough to add the extra pull for Sherlock’s final thrusts. Sherlock's orgasm is punctuated by a deep moan and head thrown back in bliss.

Afterward, Sherlock tucks John into his arms, surprising John with his desire for close proximity after the fact. They slowly sink down as a singular unit until they are atop of one of the sea mats lining the floor of the cave. Sherlock rolls them so that they are side-by-side.

Long fingers delicately probe the bite marks on both of John’s shoulders.

“They’re fine, tender, but fine,” John assures when he sees Sherlock’s knit brow.

The frown deeps slightly. “I got a little carried away.” It’s probably the closest Sherlock will ever come to offering an apology.

“Really, I liked it.” John grins. “In fact, I wouldn’t mind if you did it again next time.”

Sherlock nods, placated.

They rest on the sea mat like that for an extended time, relaxing into the newness that is ‘them’ and what they just did.

Finally, the conversation from before turns back over in John’s mind.

“You know, the dinoflagellates might not be all that complex, but they are beautiful,” John points out.


John runs his fingers through Sherlock’s hair. “Well, not everything has to be complicated or worthy of notice to be important or even relevant.”

Sherlock props up on one arm. “What point are you clumsily attempting to make?”

Even sex cannot cure Sherlock of his impatience. John should have figured as much.

“Just that sometimes even simple things are good. And that good can be good enough.”

Sherlock mulls this over for a while, then eyes John sceptically. “Are you attempting to convince me that single-celled organisms are as exciting as finding a new species of nudibranch that produces acidic mucus?”

“Maybe. Or maybe I am pointing out that simple things can lead to more interesting things, so nothing should be immediately discounted.”

This time the connection clicks and a slow grin spreads across Sherlock’s face.

“Well then, if you aren’t too tired, there are some more ‘simple things’ that warrant additional exploration, don’t you think?” says Sherlock, already swimming backwards with a cheeky smirk.

“Absolutely,” agrees John, resolutely, and follows.


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