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It’s times like these, Keigo thinks as he stares into the harshly lit ocean floor, that I really should’ve reconsidered the Commission’s offer.
In an alternate universe, Keigo would’ve been working at a small seaside aquarium that helped endangered turtles or seals or puffins or whatever. But, in Keigo’s current life, he’s stuck in a submarine observing nothing but floating sea life particles, sand, and the dark unknown.
It’s been less than a week and Keigo already regrets agreeing to this partnership.
He brushes some loose strands of curls off his face and tries not to cringe at the greasy feeling of unwashed hair between his fingertips. Even though he’s only been in this underwater death trap for four days, he’s already feeling disgustingly stinky due to the poor water pressure of the sub’s “shower”.
Yup, nothing to do all day but watch the murky surroundings and stink up the place. He really should’ve become an ornithologist when he had a chance. He could’ve been in a treehouse, high above the world, instead of in Satan's soggy asshole.
A flicker of movement catches Keigo’s eyes and breaks him out of his spiral of loneliness and regret. He peers back at his screen and spots… nothing. Absolutely nothing. All the camera picks up with their bright lighting are the large twisting rocks, the floating bits of dead plant life, and fish droppings. Even the sub’s mechanical arm is still, as if it had given up the moment they hit four hundred meters.
Still, Keigo could’ve sworn he’d seen a flicker of something. A strange light that caught the corner of the screen. A swish of something big. Something strange. Something that seemed… fishy.
Keigo faceplants into his keyboard.
He definitely regrets this partnership.
The next day in his floating prison brought another wave of nothingness.
After a quick shower in stale, weak water and a quicker meal of dry breakfast bars, Keigo had returned to staring at his monitor and playing with his paperclips. And just like yesterday (and the day before that), there’s nothing.
“Is this what hell feels like?” he asks the monitor, the swirling fish bits, the endless ocean, and the gray ceiling, “am I in hell?”
Nothing answers him back. Honestly, if Keigo’s going to be talking to himself, he might as well get up and move. Pump a little oxygen into his brain. Do some push-ups. Lightly jog to the window on the other side of the sub for a nice change in scenery. But then again, what good would going to that window do when the camera was hooked up to the computer at the front of the ship?
Bored, Keigo taps the two paper clips together before tossing them aside to find something else to occupy his time with. Reading? Nope. Writing notes? Nah. Napping? He already woke up from his mandatory eight hours so also no. Snacking? He only has enough food to last him the month and only the month so he’d rather not indulge.
His eyes drift back and forth across his desk before falling to the far corner. Innocently sitting near the desk’s edge sits a pocket-sized, four legged pink machine. A tiny mini-massager that has a deceptively high amount of vibrations packed into it. At least, he’s been told that.
His friend Rumi had tossed the mini-massager in as Keigo descended into his ship away from home. “Trust me, you’ll need it,” she said, “the chair down there hurts like a bitch.” She then very clearly looked at Keigo’s crotch, winked, and nearly closed the hatch on his fingers.
Keigo had called her a pervert over the coms as he descended.
Now he’s wondering if she had a point. Some comforting vibrations did sound nice…
Keigo quickly shakes his head, crusty curls bouncing against his cheek. No. No no no no no no. He will definitely not do the thing that Rumi thinks he will do because he is not that sexually repressed at all nope, he is not.
He tears his eyes away from the little pink devil and aggressively looks out at the ocean. Maybe, if he puts one hundred and ten percent into his job, the month will move faster and he wouldn’t be tempted to trap his chicken in a vibrating cage of temptation. All he needed to do was watch and let the deep blue unknown enchant him with its magic.
So, with determination coursing through his veins, he straightens his back and stares.
And stares. And stares.
And stares some more.
His forehead doesn’t even hurt when he bangs it on his keyboard. “You’re such an idiot, Keigo,” he hisses to himself, “Why on earth would you accept this? A month in the ocean? Really? You just had to open your big, big mouth and agree to the stupidest idea the Commission has ever had! Stupid fish! Stupid kelp! Stupid ocean!” Keigo yells, uncaring that he’s alone and pathetically trying to express his frustrations to an audience of himself.
He’s probably messing up files by head banging on so many random keys but Keigo doesn’t care. It’s not like the Commission will ever find out what kind of bullshit he pulled while on the job.
Unbeknownst to Keigo, a previously red light flickers to green and the intercom that had been switched off comes alive, broadcasting his voice for the entire ocean to hear.
The entire ocean… plus one deep sea guest.
“.... I wouldn’t say it’s that bad down here.”
Keigo freezes, his head glued to the keyboard, and a shiver tingles down his spine as a mysterious, unknown, and downright sexy voice drifts over the intercom. It echoes throughout the pod and Keigo suppresses a shudder when he realizes the voice came from outside of all places.
He looks up.
There, captured by the camera, is a huge smoky black fish tail. The tail shimmers with every twist and turn, teasing Keigo with its iridescent reflection. The tail then flicks its fins and spins, causing bubbles to erupt from its current.
“Whoa,” Keigo breathes.
A deep chuckle reverberates in Keigo’s ear. “If you thought that was impressive, then you’re in for a real treat.” The tail leaves and, with a violent pull, the expensive robotic camera arm is yanked from its resting position.
“What the—!?” Before Keigo can even finish speaking, a humanoid, haunting, face becomes illuminated in the viewfinder and Keigo nearly stops breathing when the camera focuses on what the figure is.
It’s a merman. A fucking merman.
“Hello human,” the Mer, the owner of that wonderfully erotic voice, purrs. “You sure are far from land.”
Keigo stares at the Mer’s face, at his snow white hair that shines too brightly in the darkness of the sea, at the purple scarred skin that runs across his chin and crawls up his cheekbones, at the two large, ear-like fins that emerge from the side of the Mer’s head.
The Mer’s piercing blue eyes seem to find Keigo’s through the lens and his face lights up with a fanged grin. “You getting this, air breather? Or do I need to hit this shitty camera to make it work?”
“You know what a camera is?” Keigo asks dumbly.
The merman chuckles again and Keigo’s eyes lock on to the electric blue, bioluminescent tongue that cheekily peeks out from his mouth. It’s like something out of a freaky science fiction novel or a fantasy nightmare, all long and tentacle shaped. It shouldn’t make Keigo’s dick twitch in interest.
“I’ve been around long enough to know what you humans call these hunks of metal,” the merman’s raspy voice says. “Still, this is the first time that a human actually made this machine talk.” A sly smile curls itself onto the Mer’s face and he has the audacity to slowly lick his lips, his glowing tongue sliding across skin, before saying, “You hit the ‘ON’ switch while jerking off in there?”
All thoughts of how mystically mysterious and breathtaking the Mer is immediately fizzle out and a rush of embarrassment hits Keigo like a tidal wave. “I was not!” he sputters indignantly.
The Mer rolls his glowing eyes. “Sure, and I was voted the sexiest Mer in the seven seas,” he says, his voice dripping with sarcasm. “Well, if you weren’t yanking the sea squirt, why were you banging around in there?”
“I—” Keigo’s eyes dart between the keyboard and the pink not-vibrator on his observation desk before returning to the oceanic asshole, “was… taking notes,” he says and cringes at how utterly stupid that sounds. Hopefully, the Mer will notice his awkwardness and politely choose to change topics
“Some pretty loud note taking going on there,” the Mer says impolitely, jostling the camera as he cackles, “and I don’t know of any notes that involve calling yourself an idiot Ke-i-go.”
The way the Mer enunciates his name causes an electric tingle to slide violently down Keigo’s back. A whine escapes Keigo’s lips and he hastily covers his mouth, shame quickly burning his cheeks.
“Oh? You like that? You’re sea squirt chub up thanks to little ol’ me?” The Mer’s razor sharp teeth glint menacingly in the lens. Coupled with that damn blue tongue, he’s everything Keigo’s ever wanted from a sexy eldritch horror. “Awww, that’s cute,” the Mer purrs, “I never knew humans were so easy. You land dwellers are as pathetic as slugs.”
A shudder runs through Keigo as he whines again. “Slug”. That sounds like…. Like…No, he didn’t say the other word. He said—
“Keigo? Are you still there? Or is my sea slut ignoring me?”
Shit. There it was. That magic phrase that made Keigo’s brain go extra soft and squishy with arousal. “Fuuuuuck….” he breathes, hands twitching as he lowers them, “how the hell do you know that... Scratch that, how do you know my name?”
“Hm? How do I know my slut’s name?” the Mer asks casually, as if he isn’t blowing Keigo’s mind. “Simple. I heard you yelling at yourself and it wasn’t too hard to put two and two together. As for what I assume is your favorite word….” The Mer leans in and whispers in his horribly wonderful voice, “You aren’t the only air fucker I messed with before. But, I do think you’re my favorite.”
The Mer then pulls back and, lifting the camera up, he angles it so that Keigo can see his entire body. “Look,” the Mer teases, “you’re already getting my sea squirt all excited.” Keigo’s eyes practically bug out of his head as the camera points down.
Fuck.
The Mer has a muscled white torso decorated and dotted with old scars, plump, pillowy pecs that Keigo just wants to squeeze, pointy nipples that look temptingly biteable, bioluminescent fins that pop in the camera’s fluorescent light, and... and…
Keigo’s breath hitches. If he thought that tongue was deadly, the Mer’s dick is downright hellish. In all the best ways.
“Oh fuck, fuck, fuck, fuck,” Keigo’s chokes. He doesn’t dare look away but he knows, just knows, that his own cock has taken off. “You’re a demon,” he wheezes, his gaze trailing up and down the mesmerizing neon appendage. The Mer’s dick emerges from a straining white slit, curls upwards like a curious sea monster, and shimmers a breathtaking bright blue.
Fuck… It has ridges.
“The name’s Dabi actually.”
The Mer lowers his free hand and a pleased hiss escapes from him as his tenta-dick latches onto his fingers. “Nice to meet you,” Dabi moans as he jerks himself off. Bioluminescent slick oozes from his tip, decorating his skin with what looks like glowing, radioactive slime. Keigo coos.
“That’s it slut. Keep making those sounds for me and don’t you dare look away.”
“I-I won’t,” Keigo hastily replies, mouth moving before his brain can even comprehend his words, “I won’t, Dabi.”
“Good.” Dabi then tilts his head to the side, a groan escaping him as his fingers dance across his cock. “Gods, your voice is so sexy Keigo. I hope you’re enjoying this as much as I am.”
Keigo gulps and looks down at his pants. Like a perfectly pitched triangular tent, his dick strains against the fabric of his sweats, just aching to be touched.
“Keigo? I said, ‘I hope you’re enjoying this as much as I am’,” Dabi growls. “I don’t hear any ‘enjoyment’ noises coming out of you.”
Keigo gulps again. Slowly, his fingers trailing down to his waist, he begins to shimmy his pants and underwear off. The second it's free from its cloth prison, his cock springs up like an excited jack-in-the-box. “Oh fuck,” he whispers. “I’m hard,” he whimpers.
“But are you touching yourself?”
Keigo begins to shake his head before remembering that Dabi can’t see him. “N-no I haven’t,” he says quickly. “But I-I want to. I really really want to.”
“Then go ahead,” Dabi says, “After all, I’ve already given my sea slut permission.”
Keigo throws his head back and nearly screams as he finally, finally touches himself. His rough, calloused fingers tease the pearl of precum that gathers at his slit and he wants nothing more than to start jerking it then and there.
But fuck, he needs lubrication. Or at least, something smooth and oily.
Clumsily, dick swinging in the open, he stands and, with a squawky, “I’ll be right back!” sprints to his kitchen. The shitty, soul-sucking company he works for might not provide a lot of things, but they did provide a small bottle of olive oil that he was supposed to enjoy with his rock hard bread. Not the best lube substitute, but horny beggars can’t be choosers.
“I’m back!” Keigo yells, skidding into the control room. “I had to grab stuff but I’m back now! Don’t finish without me!”
Dabi lazily looks at him, the picture perfect image of calm that juxtaposes Keigo’s crazed horniness. It was as if nothing bothered him at all and he wasn’t concerned about Keigo leaving him with his dick out. Well, technically Dabi looks at the camera. But still, the Mer’s eyes seem to once again find Keigo’s and Keigo melts at that gaze.
“You’d think that I’d cum without my sea slut?” Dabi asks, his voice dripping with mock offense. “Have more respect for me Keigo.” He lowers the camera down and Keigo nearly loses it, right then and there, as the lens is placed inches away from the Mer’s beautiful lower half. “See? I held myself nice and tight while I was waiting for you.”
Keigo almost slams into his keyboard as he slides against the slick floors and trips over his discarded pants and undies. Yet his eyes remain glued to the sight of Dabi gripping onto the base of his now even larger tenta-dick. The appendage is so large that the tip almost flicks at Dabi’s own nipples.
“Fuck… Dabi…” Keigo mewls. “Shit, you’re so big and beautiful and-and…”
Perfect. Dabi is perfect.
Scrambling into his seat, Keigo clumsily uncaps the bottle of oil. “Dabi,” he moans, hands fumbling to stroke himself as he splashes oil over his aching tip. The coolness of the lubricant provides very little relief to Keigo’s burning dick yet he still shivers at the contact. “Dabi, Dabi Dabi,” Keigo mumbles as he grabs himself and begins messily stroking himself.
Fuck, it’s bliss times a thousand and one. His hips snap up at every tug and all he can do is whine as he jerks himself off. Loud squelching sounds emanate from his hands and even Dabi raises an eyebrow, as if surprised at how fast he has made Keigo come undone.
“Slow down there, sailfish,” Dabi lightly teases, though the Mer visibly swallows after a particularly loud squelch. “I thought we were doing this together.”
“S-sorry,” Keigo mumbles, “sorry sorry sorry,” he repeats as his hand speeds up. “You’re just too hot. And sexy. And your voice sounds amazing. A-and you’re just so big. You’re…” Keigo forces himself to slow down and, in a smaller voice, says, “you’re way bigger than me.”
Dabi’s tenta-dick seems to perk up at that statement. “Oh? Am I?”
Keigo can clearly hear the excitement in Dabi’s voice and he laughs a little to himself as he thumbs his slit. Of course the super sexy Mer would like feeling superior to Keigo when it came to length, girth, and size. Then again, Keigo is the human with a size kink and, apparently, a tentacle kink.
“Yeah,” Keigo says, trailing a finger down his sensitive cock. He groans at the tickling sensation and his cock twitches eagerly. “You could probably wrap around me. Twice.”
That seems to really shut Dabi up. His mouth closes abruptly and his hypnotic blue eyes widen, as if somehow x-raying through the bulky material of the sub and locking onto Keigo’s exposed private areas.
Somehow, seeing that tiny bit of shock on the sexy Mer ushers in a new wave of confidence for Keigo.
“You would like that wouldn’t you Dabi~?” Keigo teases. “Seeing your big tentacle completely covering my dick. You could get me off and deny me at the same time.”
Feeling brave, Keigo kicks his legs up onto the desk and, lifting his hips and balancing in a feat of impressive athleticism (if he does say so himself) resumes jerking himself off. He’s not exactly sure where the intercom is positioned, but he is positive that his dick is now a lot closer to it.
“I would love that. Your tentacle wrapped around me. I bet all those pretty bumps and ridges would feel heavenly on my dick.” He tosses his head back, mentally picturing himself under Dabi, and sighs as dreamily as he can.
“…. I can vibrate too.”
Keigo falls off his chair. From his position on the floor, all he can see is the ceiling and the pink mini-massager dangling above him, having been disrupted from his tumble.
His mouth suddenly feels very, very dry as he looks at it.
Catching his breath, he slowly pulls himself up to a kneeling position and peeks back at the camera. At Dabi, methodically sliding his webbed hands all the way up and all the way down his tentacle. His tentacle that apparently vibrates.
“O-oh,” is all Keigo can say.
Dabi snorts.
“Yeah, ‘oh’,” he mocks, though his tentacle does begin to leak more bioluminescent Mer precome. “Wish I could vibrate for you.”
He says the words so softly that it takes a second for Keigo to fully grasp them. But when he does, his mind instantly goes back to the pink, not-vibrator. Standing up, Keigo looks at Dabi, then at the mini-massager, then back at Dabi, then at the massager.
He’s almost embarrassed at how quickly he caves to his own idea.
“I have something that vibrates here,” Keigo admits, his voice sounding impossibly shy. Hell, he doesn’t even recognize his own voice. “It probably won’t be the same but—”
Dabi’s eyes light up, like two bright blue fires burning on the ocean floor, and a ferociously shark toothed grin appears on his beautiful face. Keigo almost melts into a blond, chirpy puddle at the look. “Put it on yourself,” Dabi orders, “and make sure to be loud. I want to hear every single pathetic human noise that you make.”
Let no one ever find out how quickly Keigo caved to the Mer’s commands.
In a display of speed that would have any sex-lover applauding, Keigo grabs the massager and, in one fell swoop, plants his ass right back on his chair and resumes his previous position of legs up, dick free, and eyes laser focused in on Dabi. The cool, pink metal of the mini-massager sends a twitch through his cock and for a split second, Keigo wonders if he’s really going to do this. Yet all it takes is one loud moan and one even louder squelch from Dabi’s end for Keigo to finally press down on the ‘ON’ button. Hard.
A violent vibration rips through the machinery as the fully charged, super-powered massager pulsates around Keigo’s poor, unsuspecting dick.
Holy shit was it strong.
Keigo wouldn’t be surprised if the entire ocean heard him scream. For a split second, he can see shimmering, scaly fish circling his head as he comes down from what was one of the most powerful orgasms he’s had in a long time. All he can do in the next few moments is inhale, exhale, and try to reintroduce the concept of breathing back into his system. It’s only when something begins knocking into the submarine that Keigo finally comes back to himself.
The first thing he notices is that his dick is missing the massager. The second is the large line of cum splattered across his now soiled shirt. The third is the massager, lying on its backside on the ground, humming away as if nothing happened. The fourth is Dabi, smacking his tail into the side of Keigo’s sub.
“Keigo? Keigo! Seriously, you’re starting to freak me out here,” the Mer yells into the camera. “Did you zap your dick off or something?!”
Keigo can’t help but giggle when he hears Dabi’s concern. “Dick’s still here,” he croaks, “but I uh, kind of, sort of… came.”
There’s a flash of relief on Dabi’s face when he hears Keigo’s voice but it’s gone almost instantaneously, quickly replaced by a scowl.
“Seriously? You finished already?” Dabi clicks his tongue, his expression becoming annoyed and his lips pouty. “You have the stamina of a blowfish,” he huffs.
Keigo shrugs. “What can I say,” he says sheepishly, “I do things fast.”
“Yeah, well maybe you’re a little too fast,” Dabi growls, “how am I supposed to deal with this?” He gestures to his monstrous tentacle, wiggling in his hands, clearly still aroused.
A pang of guilt shoots through Keigo at those words. Shit, he didn’t mean to blue ball the Mer. He could probably recharge himself and go for a second round, but Dabi seemed to want something more than leftover cummies. If only he could somehow return the favor…
Return the favor…
A messy plan quickly forms in Keigo’s brain and all he can do is shudder at the idea. Well, horniness has gotten him this far, so he might as well go all out.
“....do you mind swimming around to the back of the sub?”
A confused look crosses Dabi’s face and Keigo mentally pushes down his own nervousness. “Leave the camera and swim over there,” he says, “just… trust me on this.”
Then before he can overthink it, Keigo stands, grabs the massager, strips out of his shirt, and walks as confidently as he can to the other side of the sub. Flicking on a light switch, he heads towards the sub’s other observation window and, with a final deep breath, presses the button that turns the glass from dark to clear.
It takes a few seconds for the Mer’s eyes to acclimate to the bright flash of light coming from the underwater machine but once he does, all he can do is stare at the naked human he had been teasing for over an hour.
Keigo waves at him, feeling incredibly awkward as he shows off his bits to the mythical creature in front of him. But as he watches Dabi swallow, his blue eyes moving up and down in awe, Keigo can confidently say that he made the right choice.
Dabi licks his lips with his long tongue and Keigo’s eyes follow the movement hungrily, his dick giving a small twitch in interest.
“No turning back now,” he tells himself. He steps closer to the window and carefully pushes his body against it, making sure his pecs press against the glass. Although he’s not as endowed as Dabi, Keigo can confidently admit that his tits can put on a good show. A great show even.
Finally, Keigo adjusts the settings on the vibrator from dick-destroying to light pulses and winks at Dabi. He indulges in the look of understanding that crosses the Mer’s face then lowers the massager back onto his cock.
This time, the calmer vibrations allow Keigo to enjoy the sensations better. He rocks his hips back and forth, his dick sliding against the massager, all while making sure his chest is still perfectly squished against the glass. He rolls the massager across his length, over his tip, and even presses it against his balls. Then, because he is a little shit, he dramatically thrusts into the pink toy and gives Dabi his best, and sluttiest, grin.
Even though he can’t hear Dabi, Keigo can tell that the Mer is growling as he watches the human pleasure himself. Dabi then begins to jerk himself off in tempo with Keigo’s movements, precome bubbling out of his tenta-dick. Then, to Keigo's delight, Dabi begins to jerk himself off in tempo with his movements and a steady stream of precome bubbles out of the Mer's tenta-dick.
Oh, how Keigo wishes he could touch it. Let that tentacle dick tickle his fingers. Let it tickle his mouth. Let it tickle his dick. Let it run up the curve of his ass, wiggle in between his cheeks, and plunge into his insides. He wants to ride that big eldritch bad boy and feel it lash against his prostate as it stretches his hole beyond repair.
He wants to be the perfect, human-shaped toy for Dabi and his perfect cock.
His eyes meet Dabi’s and a silent spark of understanding and want jumps between the two of them before they’re both coming apart.
They stay there panting, Keigo’s second round of cum dripping down the window from the inside as Dabi’s more colorful ejaculate coats the outside.
Keigo’s legs begin to quiver and he presses a shaky hand against the window to steady himself. He’s fogged up the glass thanks to his tit grinding and he can’t help but blush as he pulls his chest back, his nipples clumsily becoming unstuck. Fuck, he’s going to have to clean everything before management finds out.
Then, to Keigo’s surprise, a clawed hand presses against his own. Keigo’s eyes widen and they travel from the hand to its owner. To Dabi.
Bubbles surround the Mer’s beautiful body in a curtain of oceanic heat. His tentacle is the picture of satisfied calm. And his face… Fuck… Dabi really is gorgeous. He really is…
“Perfect. You’re perfect,” Keigo breathes.
Dabi merely tilts his head and grins a lazy, toothy grin at him.
Keigo doesn’t know how long he stands there with his hand pressed against Dabi’s. Maybe minutes. Maybe hours. But eventually, Dabi flicks his tail and floats back, which Keigo takes as his cue to also step away. He shivers at the drying sensation of cum on his body and, suddenly feeling shy, covers his limp dick as casually as he can.
Dabi rolls his eyes and scoffs.
“Well excuse me for having some decency,” Keigo grumbles before remembering that right, Dabi can’t hear him anymore.
Still, Dabi seems to get what he’s saying and, in a move that will forever haunt every single one of Keigo’s wet dreams, creates a v-shape with his fingers and slides his tongue between them. The long appendage wiggles between the two clawed digits and instantly sends Keigo spiraling.
Dabi then has the audacity to laugh at whatever bug-eyed, gaping expression Keigo makes before dramatically mouthing something out to the human. With a final cackle, Dabi flicks his tail and zooms away, leaving nothing but a cloud of bioluminescent cum in his tracks.
But all Keigo can see is that tongue, those fingers, and the Mer’s final words.
“I’ll be back tomorrow, slut.”
Keigo can’t help but smile. This is going to be a very, very fun month.