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Keith knows he has gone too deep when he starts to see the bones.
They litter the seafloor and the shelves of rock and strange coral growth which jut out from the dark water like so many teeth, innumerable and gleaming, stripped clean of flesh. There are bones from all kinds of creatures, big and small. He sees the long, twisting vertebrae of oarfish, the serrated teeth of sharks, the porous scutes of sturgeon first. Then, others emerge from the muck: the tiny skulls of puffers and anglers, the carapaces of crabs, and even the massive ribs of a long-dead whale which surrounds Keith like a macabre cage as he swims through the slender, yellowed skeleton, heart pounding.
He has gone too deep, and his instincts are torn, the fear of being chased by the other Mer driving him further forward, further downward, even as the fear of this graveyard he has stumbled into fills him with a growing cold. Eventually, Keith slows, glancing about – he can see in the dark, but not in this dark, and the realization freezes him.
Every Mer worth their salt knew to stay well away from the depths and the creatures that lay within.
And because every Mer knew this, the depths are the very place they’ve chased Keith into...he shivers, wrapping his arms around himself, barbed fins fluttering with anxious adrenaline. He should leave – return to the shallows and find a cave to hide in, and hope that the other young Mer who have made it their life’s goal to torment him don’t find him.
Something moves in the dark water.
Keith goes still, save for his gills, which flutter frantically, gulping in the scarce oxygen. His eyes dart about, and he curls his tail in front of himself, defensive, the venomous spines in his lionfish fins at the ready. But he fears the threat will do little to deter whatever monsters live down here. Food is so scarce as it is; some flashy colors and stinging venom will hardly scare them off from a tasty Mer meal. Maybe his blade will be more effective.
Just as the thought crosses his mind, a shadow flickers through the water and binds his tail faster than he can process. Panic jolts him, urging him to flee, but Keith can’t free his tail from the powerful grip of – whatever’s caught him. He unsheathes his blade, intent on slicing the strange appendage away, but another one darts from the nothing surrounding him, knocking his blade free. It sinks, its glowing violet hilt fading into the darkness, and Keith flails for it, but as he reaches out...his fingertips make contact with flesh.
“Fuck,” he whispers.
He’s straining to see what exactly he’s touched, when all around him pale blue-white lights illuminate, one after the other, revealing long, softly undulating tentacles, arched up around him in an inescapable net. And as Keith looks up, at once aware of a huge, terrible presence just above him, two glowing red eyes stare back down at him.
Keith screams, thrashing in the creature’s grip and trying to pierce his spines into every bit of twisting, dark flesh that grasps at him. He freezes when a low, sonorous growl surrounds him, the red eyes narrowing, blinking, peering closer. As they do, Keith realizes their red glow is more like a strange magenta, with bright golden pupils that dilate, fixed on him.
The creature – monster, surely – is huge. But it’s also unexpectedly Mer-like. Yet...not. As it looms over him, Keith sees more of it revealed, illuminated by the eerie glow. Its ears are like his own, with many-pointed fins. Its torso is masculine, more heavily-muscled than any Mer that Keith has seen, but close enough. But its tail – it doesn’t have one. Instead, its torso shifts into thick, dark tentacles, its lower body resembling the largest octopus Keith has ever seen, and quite possibly the largest octopus in the entire damn ocean.
The creature stares at him, lights pulsing in a curious rhythm, a tentacle wrapped fast around him, not reacting at all to the lionfish stings, other than with the initial growl. The creature’s face, Keith thinks, unbidden, is weirdly beautiful. Framed by a silvery forelock and long dark hair drifting around sharp cheekbones, a thick scar slices across its nose, but the rest of its features are almost delicate, offset by its strong jaw and the dozens of jagged, glinting teeth revealed as its mouth opens.
“Please don’t eat me,” Keith says, struck by the wild thought that if this creature is even a little, tiny bit like a Mer, it might listen to reason.
The creature hums, tilting its head. Then it reaches out with one of its tentacles, and Keith sees something in its clutches – his blade. He’s struck with dizzying relief that it wasn’t lost to the deep, then horror as the creature passes it from a massive tentacle to a just as massive hand. It holds up the blade with a sound Keith swears is questioning and says, halting but intelligible, “Hunt?”
Keith blanches. “Hunt? No – no, I’m not hunting you!”
The creature blinks at him, digesting the words, and then it makes a strange, burbling sound. Keith holds himself stiff and uncertain before he realizes why the creature is shaking and rumbling like it’s laughing. He? Is it a he? “No,” the creature finally says, sharp teeth stretching wider in a wicked smile, “you are not.” He leans in very close, too close.
Keith gulps. “Are you hunting me?” he whispers.
There’s a look in the creature’s eyes. Almost thoughtful, definitely curious. Okay. Okay, Keith can work with curious.
He’d be lying if he said he wasn’t curious, too. More tentacles have joined the first, and though they’re wrapping around him, ensnaring him, they aren’t bruising in their grip. They feel exploratory. Gentle, even.
But that’s a ridiculous thought.
Then the creature pauses, smile falling, brow furrowing. It growls again, and when it shifts forward, bringing Keith fully into its space, he fears this is the end. When it opens its mouth and aims for his chest, he’s certain of it, and braces himself to be torn into.
The pain never comes. Instead, Keith finds himself licked.
“What,” he yelps, high and embarrassing, voice cracking with terror and confusion and – maybe something else. The creature’s tongue, which is long, thick, and also faintly glowing, drags over his chest, leaving a faint bioluminescent slime behind. It’s tingling, and shockingly warm in these cold depths. Keith shudders, jerking uselessly in the creature’s grasp.
“Hurt,” the creature says, licking again, more of a soft lap, this time, and Keith looks down and realizes the creature is licking at the fresh slices across his chest, left by his bullies’ claws before they chased him here. “No hurt.”
This can’t be happening. “I – you’re not – going to hurt me?”
The tentacles squeeze around him, somehow, impossibly, reassuring. “Protect,” the creature says simply, nuzzling at the wound, then looking up at him with wide, magenta eyes. “I am Shiro. You are pretty.”
Keith’s gills lock up and for several seconds, he chokes, spluttering, until he finds his voice again. “Pretty? No – no, I’m Keith! KEITH!”
“Pretty Keith,” Shiro – its name is Shiro? – declares with an affectionate squeeze. Affectionate? Wait. Wait.
Keith’s mouth hangs open. “You’re...not hungry?”
“No. Not hungry. Can eat everything.” Shiro makes a mournful sound. “Lonely. Cannot mate everything.”
MATE? “Oh,” Keith says, his voice sounding very distant. “Well, that’s…”
“Could mate you?” Shiro says, hopeful, and the slime on Keith’s chest is tingling worse than before, filling him with a spreading warmth, as terrifying as it is alluring. “Like me. Small, but...pretty. Pretty Keith.”
But Keith shoves the sensation and Shiro’s tentacles away, frantic, seized by a feeling that is not nearly as horrifying as it ought to be. “No!” He thrashes in earnest, heart pounding and blood roaring in his ears even as the slime makes arousal stir hot and shameful in his belly, and below. “Let me go!”
He does not expect Shiro to release him as if stung – technically, he has been – shrinking back with eyes even wider than before, relinquishing his grip entirely. “No?” His voice has no right to sound so small and pathetic. “But – no hurt...”
Keith isn’t listening. He turns tail and flees, swimming for his fucking life, blade be damned. At any moment, he expects a tentacle to lash out, to hold him fast and drag him back down to his death.
But it never comes, and when he reaches the continental shelf, he clings to it like a limpet, curling up in a tight ball of quivering spines.
He wills himself to forget those wide, earnest eyes.
It doesn’t work.
*
Keith tries to wash the slime off, but it lingers through several scrubbings, and by the time he thinks he’s removed it, his torso is raw and red and the tingling hasn’t subsided; it seems worse than before. Instead of returning to the reef, Keith stays curled in his shelf cave, drifting into uneasy slumber in the hopes that this strange spell will pass when he wakes.
It doesn’t. He wakes to his cock unsheathed and harder than he can ever remember, and what’s more, his slit is soaking wet, and when he presses tentative fingertips to it, the slickness reminds him of Shiro’s slime and it’s all over after that. Keith muffles his cries in his fist, his other fist filling himself, thrusting in and out in a poor imitation of the sinuous, powerful rhythm one of those dark tentacles would have. The thought makes him scream behind his gritted teeth, eyes rolling back and cock swelling, its red, twisting length seeking the heat of his own hole. Keith lets it, reduced to a mess of moans and trembling by his own touch, and he comes with a faint, wordless keen like that, his cock doing its best to fill his aching slit, his fist keeping himself stuffed.
Afterwards, he lays there sore and shocked, staring at the rocky ceiling. What has Shiro done to him?
*
Keith wonders this for weeks afterwards, long after the slime has worn off. He just can’t stop thinking about it. Not just about that weird, wonderful, warm tingling, but about how hopeful Shiro had been. How... sweet. He had wanted Keith. No one wanted Keith.
So maybe a giant eldritch monster of the deep wasn’t an ideal catch; but, maybe Shiro would have eaten another Mer, one who wasn’t so pretty.
Or maybe he was just desperate and Keith was the first unlucky one to stumble into him. Yes. That must be it. Who is he kidding? He isn’t pretty. He’s a warm body, that’s all.
Shamefully, even this thought does not dim his desire.
The next time one of the crueler Mer chases him to the edge of the reef, and further, to the edge of the shelf, Keith flees into the depths again, unsure of what to expect, except that he doubts he will return to the reef.
There’s nothing for me there, Keith thinks with no small measure of bitterness as the sunlight fades and the dead sea rises around him in an inky void. His face stings where one blade had caught him – they’d gotten nastier after he returned without his own blade, needling him with insults about how he couldn’t even do that right – and a dozen other scratches litter his body from the scuffle that had prompted his flight. At least Keith left his mark on plenty of them, too. Their blood flakes from under his nails as he dives deeper, the pressure threatening to crush him as before. Keith half welcomes it.
The sea grows cold, silent as a grave, and uneasiness sets in. What is he doing here? The sea is immense, and even if he were to find Shiro, what then? He had rejected Shiro, fled from him – he doubts Shiro will be pleased to see him.
So he will either be eaten, or...something else. Keith curls his fins closer around himself. He was foolish to have returned. But if he returns to the reef, they will only mock him more fiercely. Keith is not one of them; he was an infant stolen by accident from an enemy clan on a raid, hidden away as he was in a basket of clams. The Mer who stole him only wanted the clams, not the pup, but they had been unable to kill him, so they kept both.
Keith is certain they enjoyed the clams far more. Keith has been a thorn in their side since his unwilling arrival; they will be glad to be rid of him. The clan he was born to has long since dissolved, most dead, the rest scattered to the tides. Keith belongs to nowhere, and to no one. Perhaps it’s fitting that the deep takes him, for better or for worse.
Something glows in the darkness. Keith pauses, squinting at the light. It’s the right color for Shiro’s, a faint blue-silver orb floating. He can’t tell if it’s tethered to a tentacle, but it doesn’t look like an eye...Keith swims towards it, cautious, but inexorably drawn. He swallows, gills fluttering. “Sh...Shiro?” he whispers. “Do...you remember me?” The light bobs slightly. Just a little. Is that a yes?
He nears the light, frowning. “Hello?”
It’s then that he sees the teeth. Much bigger than Shiro’s, longer and thinner like needles, they line a great, gaping maw. The light dangles in front of it, a deadly lure, and Keith is too close.
A furious burbling snarl cuts through the grim quiet, and Keith jerks back as eight thick tentacles slam into the ugly head lying in wait before him. The light sputters out as the predator flees from its ambush point in a cloud of silt and bone fragments, its illumination replaced by dozens of glowing dots. Keith turns to face their owner, still shaking, and sure enough, magenta eyes meet his. They aren’t angry, as he had feared; they’re concerned.
“Keith,” Shiro says. He does not grab Keith this time, but lingers, gaze sweeping over him. “Hurt,” he adds, shoulders slumping. “Waited for you…”
Keith hunches. “You – you did?”
A small nod. “You left this.” One of the smaller tendrils uncurls, holding out Keith’s blade to him. Shiro keeps his head bowed. “Yours.”
“You kept it?” Keith takes the blade with unsteady hands. “Thank you…”
Shiro nods, glances up at him. “Goodbye, Keith.” He turns to go, tentacles drooping.
“Wait!” Keith winces at how desperate he sounds, but it’s honest. Shiro goes still, looking back at him, uncertain. “Don’t go, I – you’re right. I am hurt. My clan, they hurt me, and if I return, they’ll hurt me more. I can’t go back. I – I’m alone. Like you.”
Shiro blinks. He hesitates, then says, “You are alone...and you found me?”
“Yes.” Keith winces. This was stupid. “Look, I don’t want to bother you, I just thought, maybe —”
“No bother!” Shiro exclaims, and there’s something in his voice, a nervous, excited note that catches Keith off-guard, like everything about this strange being does. Shiro offers him a smile, but tiny this time, and close-lipped, as if to avoid scaring him. “Happy you are here, Keith.” He shifts forward, pauses, hovers with his tentacles outstretched and anxiously wriggling. Slowly, he extends his hand. The other, Keith notes, is more tentacle than arm, but...it isn’t unpleasant. More...thought-provoking.
“Protect?” Shiro offers.
A weirdly earnest, undeniably handsome monster of the deep is offering to protect him. Well, then.
Keith hesitates, then swims a little closer, then closer, until he’s almost right up against Shiro, blinking up at him, those dark tentacles arcing around him with curious, longing wiggles. Shiro’s eyes go very wide when Keith reaches out to touch one of them, his fingers coming away with that same faintly glowing slime. Shiro lets him, holding very still, as if he expects Keith to flee at the slightest movement. Keith probably should… but that’s not his intention.
He swallows, gills fluttering. “Maybe you can do more than protect me,” he whispers. His eyes dart up to meet Shiro’s, and he watches that worried gaze shift into something different. Surprise, curiosity, and then heat, lust, want ; yes, Keith can admit it. It feels good to be wanted, for once.
Keith is prepared for more cautious questions, more careful movements, but instead, he feels tentacles coiling around him, one after the other, grasping his tail as if it isn’t covered in venomous spines, as if he is soft and precious and meant to be held. Keith would be lying if he said he didn’t like the feeling, new though it is. Maybe, he can be those things for Shiro. He likes the thought of being soft and precious to someone, laughable though it seems.
But Shiro isn’t laughing. He leans in. “Take you somewhere safe,” Shiro says, a low rumble that Keith feels in his belly, where warmth is stirring just from the proximity. He feels it in the steady tingling in his fingertips where he touched the slime, too. He feels it spread thrumming and hot all over him, or at least to every point where Shiro’s tentacles wrap and slide and pulse around him with heavy anticipation.
Keith stares at him and nods. “Yes,” he says, shuddering when Shiro’s grip on him tightens, ripples.
Shiro rumbles again, wordless this time, and then Keith is enveloped, drawn hard and fast against him, and Shiro is surging through the dark water with impossible power, the speed and strength in his massive form dizzying as Keith clings to him. By the time Shiro slows, their surroundings have changed. Gone is the open ocean and the desolate sea floor, replaced by a cave of some kind, its walls adorned with all manner of strange life, like coral but alien in its structure and bioluminescence. It makes Keith’s vision blur and his mind swim in a not unpleasant way to look at them for too long.
Shiro settles them in a shallow bowl dug out of the sand towards the back of the cave, and he cradles Keith in the center of his curling and uncurling tentacles, making odd cooing sounds over him. Keith glances about, then back up at Shiro. “Is this your home?”
“Yes. And yours,” is all Shiro says, and Keith finds his face encircled by claws as Shiro’s hand lifts up to his head, claws tracing over his skin, studying the fresh wound with a loud growl. When he leans in to lick at it, Keith expects it, but Shiro’s tongue is so large that it laps at the corner of Keith’s mouth; it’s only natural then for Keith’s lips to part and for him to lick back, clumsy but with more confidence.
Shiro hums, tilting his head, and then his tongue is slipping past Keith’s parted lips, filling his mouth with its hot, twisting length. Keith moans around it, slumping into him as his entire throat begins to tingle and warm; he pushes his chest out without a thought, scrabbling at Shiro’s front, seeking sensations he has no name for.
Shiro coos again, the vibrations thrumming through Keith, and when Shiro pulls away, it is only for a moment, only to seize Keith and turn him so that Keith’s back is flush with Shiro’s chest, his tail and the swelling slit atop it, now vulnerable and exposed, helpless to hide from Shiro’s wandering tentacles. But Shiro doesn’t touch his slit with the tentacles – it’s his hand that rubs over it, claws teasing at the slick flesh as it opens with growing arousal. Keith whines, uncertain, staring at those thick clawed fingers, each one so much larger than his own. “Shiro,” he gasps, “what are you –”
Shiro licks a long, tingling line down the side of his throat and Keith goes limp in his grasp, gills flooded with – whatever magic it is that Shiro possesses. “Safe,” Shiro murmurs, nuzzling into his neck, his hair, his back, like he can’t get enough. “Keith, Keith. Pretty Keith. You want this. I have you.”
And he really does, because the next moment there are two fingers sliding into Keith’s slit, splitting him wide, wider than he’s ever dared to start with when teasing himself. Keith’s eyes fly wide, tail thrashing and mouth falling open, Shiro’s fingers working inside him in a way that is both tender and brutal. Keith is making sounds, so many sounds, and rather than hush him, Shiro purrs in encouragement as he begins thrusting his fingers in and out, squelching with how wet Keith has become, fucking him on two fingers with enough girth to be a Mer’s cock.
Speaking of which, Keith’s cock is unsheathed and dripping, and Shiro’s tentacles seem to delight in it, covering it in thick coils and stroking it in a way no hand ever could. Keith melts into the touch, so overwhelmed and bewildered and aroused that he can do nothing else. Was there ever anything, really, before Shiro? His mind falls away to delirious thoughts like this one, the longer Shiro touches him, the closer Shiro brings him to the edge. Shiro adds a finger and Keith screams; he adds another a small eternity later and Keith is squirming, begging for more, his stuffed slit aching as he tries to fuck himself on Shiro’s fingers. It’s now nearly his fist, and it’s this thought that makes Keith come for the first time, whimpering and pleading.
“Good,” Shiro says, and sharp teeth graze over Keith’s gills, the near-slice of the sensitive flesh making Keith burn ever hotter. “Again.”
Keith moans, shaking his head. “I don’t know if I can – ah…”
Shiro’s tentacles squeeze his cock in promise. “You can.” Shiro’s fingers start moving again, thrusting slowly and purposefully. “You will.”
And when one of the thicker tentacles nudges at Shiro’s fingers, intent on wriggling in alongside them, Keith believes Shiro wholeheartedly, because he never knew that he would like being stretched so wide, but as it turns out, he loves it. His second climax comes moments after the tentacle finally works its way inside, making his slit bulge and twitch from the pressure, his cock splattering and spilling as Shiro’s other tentacles obediently attend to it.
The third time Keith comes, it’s after Shiro has replaced his fingers with tentacles, and they take turns fucking Keith open, playing with the swollen folds of his slit as it struggles to tighten and close around each new, delicious intrusion. Keith’s arms are bound by the other tentacles, and one has coiled around his throat, and another binds his tail fast, but he does not try to escape.
As relentless as Shiro is, there is a sweetness to the onslaught. Shiro is not a Mer; he does not think like a Mer, and he does not fuck like a Mer. It occurs to Keith that Shiro’s kind take what they want, and they take it completely. You want this, Shiro had said, with absolute certainty, and he was right. Keith shakes and opens to another tentacle, cock leaking and twitching, and he can’t deny that Shiro was right. Keith returned to the deep for a reason, and now – perhaps Shiro will keep him here like this, bound and fucked forever, and in that moment, Keith can’t object.
But Shiro does not do that. Instead, when Keith is reduced to babbling and flopping uselessly in his lap, Shiro gently pulls him back around so they are face to face and kisses him, deep and slow. It is a grounding kind of kiss, one that Keith never expected from the creature that has spent the last hour utterly undoing him, but it has the intended effect: Keith is soothed, sinking into Shiro’s weird, warm, wonderful embrace.
“Good,” Shiro says when they part, tentacles stroking over Keith’s skin with unmistakable tenderness. He tilts his head, a bit of worry creeping in as he repeats, questioning now, “Good?”
Good does not even begin to explain what Shiro has made him feel, and Keith suspects this is only the tip of the iceberg of what he will feel with the strange, terrifying, lovely being called Shiro.
But he nods, lets himself nestle closer, lets himself relax into this strange new life he dove headfirst into. “Good,” Keith agrees, and lays his head on Shiro’s chest, hiding his helpless smile there. “Yes.”
And it is.