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“Fuck, wait-Lance!” Keith’s words were useless as the merman hands were already all over him. He had barely gotten ankle deep in the water when the massive creature had pounced on him, dragging him farther out and Keith was so, so grateful that they agreed to meet on a private part of the beach near Shiro and Allura’s house, because he really did not want to have to explain a ten-foot-long merman groping at his ass to his older brother. Or to anyone at that matter.
But for some reason Lance had been antsy lately, even when they were fully underwater his tail had been twitchy, betraying his smooth easygoing attitude and smile. His grip had slowly become more and more possessive on Keith’s body until one day his fingers had left prints on Keith’s left cheek, making him flush softly every time he sat down. But every time he had asked, Lance seemed to have avoided the question expertly.
That is, until now.
“Goddammit, Lance!” A swift smack to Lance’s head had the merman whining, a rough tongue licking Keith’s collarbone with far more vigor that it should have been. Keith was no dessert, thank you very much. “Would you stop grabbing my ass for one second and tell me what the hell is going on? What’s with you today?” He watched the Merman as his eyes opened, and Keith’s breath caught in the salty air around them as Keith’s beautiful blue hue had changed into pure black, not even the whites of his eyes were visible.
“Mine.” Lance had growled out, and Keith’s eyes widened as Lance licked his skin again, too stupefied to say anything at the moment. “My mate.”
Okay. Keith should probably explain.
Shiro and Allura had gotten married, and Keith had been invited to live with them in a place called Veradera beach, right near a private part of said beach. Allura’s parents were loaded, and Shiro seemed not to have realized that until after the wedding, only making Allura fall in love with him even more. And while he was out walking on the beach at night, he had heard a splash, turning around to see something that made him wonder if there was actually crack cocaine in his soy milk that evening.
It was a mermaid. A massive fucking mermaid. light blue scales glittered in the night, almost as if they were part of space themselves, disappearing into copper skin at the waist, some scattered on his elbows and his back. There were, surprisingly enough, two sets of gills, one on his waist and one on his neck, appearing where ears fanned out into fins, like arched translucent cuffs. And the mermaid-merman was stuck in a net. A fisher’s net.
“Holy shit.” Keith mumbled to himself as he rushed over, blinking quietly at the sight before him. He watched to see if the creature was still breathing, and when he could see the gentle rise and fall of their body, he quickly fell onto his knees and started cutting the rope with his knife, concerned even though he was nearly positive that this was some sort of hallucination and he’d be seeing pink fairies flying over any minute now.
He was on his last part of the rope when suddenly the massive body was over him, and he was pinned by one massive tail pressing against his abdomen, making it hard to breath. Dark brown hair dangled lightly in front of him, smelling of saltwater and what Keith imagined the darkest part of the sea would be like. Bright blue eyes were sharply focused on him, taking him in and Keith knew in an instant that there was no fucking way he had made this… this merman up. “Well you’re certainly a sight for sore eyes.” Keith’s eyes snapped away from The merman’s massive chest and up to look back at the sharp grin (he really meant sharp. They looked like shark teeth) aimed at him, eyes lidded. “Or a sore merman.”
“Ex-excuse me?” Keith had managed to stutter out, eyebrows furrowed as he sputtered.
“The name’s Lance.” The mermaid continued to speak as if he didn’t hear Keith’s sort of question. “I’m not usually into humans, but for someone as cute as you, I could make an exception.” His wink made Keith’s cheeks burn slightly as he tried to move, but the tail was so heavy he could only strain himself in the movement. “Your name is?”
Keith couldn’t escape, couldn’t get out of the merman’s-Lance’s grip, so with a defeated little flutter, he let himself relax. “Keith.” He mumbled. “Keith Kogane.”
“Nice to meet you Keith! I believe now we shake hands.” A webbed hand was stuck out, and with a sense of bewilderment that was rapidly becoming normal, Keith reached out and shook hands with him the webbing slightly gooey but not enough to make him full body shudder, like snails.
Fuck snails.
“You come here often?” Keith came back from his own thoughts to Lance wiggling his eyebrows at him. Keith couldn’t help but roll his eyes.
“Great. I’ll be back tomorrow then. Same place? Seems pretty secluded.”
“Wait, what?” But the mermaid was already off of him, sliding back into the water and using his tail to push himself up to his full height, a couple heads taller than Keith. Holy shit. “What do you mean?”
But he was already gone, a shimmery blue scale resting in the sand and later on resting on Keith’s new bookshelf as he lied awake, staring at the soft waves almost lovingly caressing the sand underneath them.
And then it became a reoccurring theme, reoccurring enough that night time rendezvous would turn into daytime rendezvous and eventually all dayzvous. They slowly and steadily learned more about each other, about Lance’s curiousity for humans (or Split Fins, as he called them) and Keith’s… questioning of his sexuality.
And that’s when it all changed.
“Wait, so you can only choose one sex to be attracted to?” Lance’s disbelief was palpable through the vowels as he spoke, watching Keith kick the sand around him and toy with a few shells Lance had picked up for him from the lower reefs. “Why?”
“I mean, some people like both? Or all? I just… I just don’t think I do.” Keith sighed, watching Lance’s tail slowly sway side to side. “I’ve never been with anyone, and I’m not sure I trust anyone enough to try. Girls are nice, but…”
“How about with me?”
Keith’s head snapped up. “What?”
Lance leaned closer into the sand, eyes lidded. “I’m male by your societies’ standard, yeah? Come on out here and kiss me. See how it is.”
Keith’s cheeks turned a hot pink, and he looked down and away. “What if your lips are gross and slimey?” He said a bit childishly, and when Lance laughed at him, he scooted closer despite himself. “What?? I don’t know!”
Lance raised one amused eyebrow at him before pushing himself forward enough that he was suddenly looming over Keith, practically hiding him from the hot Cuban sun. “Why don’t you come find out, lover boy?”
Keith swallowed at the suddenly deeper voice Lance seemed to have, and with a careful movement, Lance pushed back into the water, stretching his hand out. After a moment of hesitation, Keith took it, and Lance’s free arm wrapped itself around Keith, tugging him close. “You’re so soft.” Lance murmured into Keith’s ear, and he shivered at the sound, pupils dilating almost immediately at the sound, surprisingly smooth fingers rubbing circles into his side, making Keith relax almost immediately. “I want to try something. No matter what you do, don’t stop kissing me, okay?”
“Wait, wha-” And suddenly they were underwater, and Lance’s lips were pressed to his. Keith accidentally gasped, but instead of water in his lungs fresh air billowed out from Lance’s lips, and Keith was breathing underwater. By kissing Lance. The arm tightened around his waist and Keith couldn’t help but fall into the surprising softness of the merman’s lips that so eagerly pressed against his, mouthing at his lower lip and tugging a little wit with a sharp tooth. Keith had suddenly found himself with his hand in Lance’s hair and another on his gills, and judging by the way that Lance’s movements stuttered as Keith’s fingers grazed his upper set of gills, he knew that it must have been a good spot to catch. So he kept touching and kissing until the airflow between them stopped abruptly, a hand reached down to grab his ass and squeezed, and Lance had bitten down on Keith’s lip hard enough to bleed.
Keith managed to shut his mouth in time, but Lance was suddenly ravenous on Keith, mouth leaving the human’s and suddenly trailing right to where the juncture of neck and shoulder were before licking it and sinking his teeth into the side. Keith couldn’t stop his failed cry if he tried, all the air leaving his mouth as he went limp in Lance’s grip, body screaming without oxygen to support it. The world around him was going dark, and he let his eyes close. Yes, everything would be fine, if he just took a nap…
But he was rudely awakened by air rushing through his lungs and sand getting tangled in his hair. He coughed loudly and rolled over to his side, lips cracked and eyes red from the salt. It took him a while to understand why the right side of his neck hurt so much, and when he touched it he hissed at the slight pain that radiated from just a gentle touch. “Fuck, what?...” He sat up and looked up over to where Lance was supposed to be, only seeing a tail raised in the air as he disappeared into the waves. Keith watched him with a confused expression, the mark throbbing with the pulse of the waves that had very nearly claimed his life that day. Of the mermaid that had very nearly claimed his life that day.
Lance didn’t come back for two weeks. Keith had come by every day, despite the voiced concerns of his brother and sister in law at the large bit mark that rested on his body. It always throbbed at night, sometimes leaving him hard and breathless, and sometimes it would almost violently pull his body into writhing into the sheets beneath him, longing for the roughness of the sand on his back and scales scraping his front. He decided to ignore it until Lance came back, and even then Lance acted like everything was normal. Sure, they’d known each other for quite some time that Keith knew there were some questions that he shouldn’t ask, but Lance had marked him. Marked him in a way that he knew must mean something, considering the way that Lance’s eyes and hands trailed to it. Every single little touch that was pressed there by Lance had Keith’s back twitching, as if begging to be arched and his legs spread. He flushed hotly at that, only recently having found the idea appealing in any way. But the more Keith tried to bring it up, the more Lance avoided it. Keith even tried keeping Lance at the beach, but that only ended with Lance nipping at the bite and squeezing his ass so hard he saw stars, breath leaving him in a big burst of air. It was only until after Lance left that Keith realized he was twitching in his swimsuit, dick drooling at the contact. He flushed wildly before managing to stand up, almost stepping over the writing in the sand.
‘Meet me in Arus Cove tomorrow evening.’
Which brought them back to the present, Lance’s mouth on his neck, hand on his ass, and tail grinding between Keith’s legs. Ah, and the mate part. That was new too. “Keith.” Lance’s voice was dark, but his eyes had returned to normal, only a little larger than usual. The cove was hidden from any prying eyes, and Keith had to thank Lance for thinking of it. Here, nobody would bother them. Lance could keep grinding into him just like that, and oh.
For a wild moment Keith thought Lance had a mini tail. Or an extra fucking limb. But when he looked down, he saw a monster of a glowing cock roughly the size of his own forearm. It writhed in the water, and Keith could only swallow and stare nervously at it with wide eyes. “Uh…” He trailed off awkwardly, unable to really think of anything to say in the situation. “Is that…”
“My dick, Keith.” Lance’s voice was impatient as he pulled Keith closer into the water. “That’s my dick. Don’t beat around the bush.” As if it knew they were talking about it, the appendage was suddenly rubbing against Keith’s crotch, making an embarrassingly high pitched yelp leave the human’s mouth. Lance moaned at the friction, and Keith could only feel his eyes lid as Lance’s lips descended to his mark once again, licking and sucking on the scar until it was covered in hickies and Keith was moments away from cumming. But Lance pulled away, Keith’s body instantly missing the feeling. “Keith. I need you to let me fuck you.”
Keith’s brain stuttered to a halt almost pleasantly. “You-what?”
“I marked you.” Lance seemed practically desperate now, his hips pistoning forward at an almost ridiculously fast pace, and Keith could only let his head fall to the crook of Lance’s neck, his breath fanning over Lance’s gills and only making him groan and have both hands fall to Keith’s ass, massaging and squeezing until Keith keened. “You’re mine. It’s ahhhfuck, it’s mating season. Please?” A finger slipped under Keith’s swimsuit, and the raven haired man keened as a finger pressed against something that he knew for a fact was not supposed to be that wet and sensitive. “You’re already dripping for it.”
“Motherfuck, Lance, what did you do to me?” He couldn’t help but whine, hips unintentionally moving back against the digit, groaning in relief as the webbing seemed to yield to his eagerness, and a finger pushed into the hilt, making his head fall backwards as he tried to regulate his breathing. “Humans don’t fucking self-lubricate!” Lance’s finger began to piston and Keith made a noise that he refused to call a whine. “They don’t!”
A second finger entered while Lance mouthed at his neck a little bit. “The mark. We mark our intended, and the chemicals inside do the rest, preparing our mates for mating. Which means for humans…” Two fingers pressed against something inside of him had Keith crying out, his voice echoing embarrassingly in the cave around them. “…That their bodies become more suitable for copulation.” A third was added, and Keith was ninety percent sure that he was drooling into Lance’s shoulder, eyes glassy and breathing heavy as he felt himself spread his legs wide enough that Lance could easily press forward, ripping the swimsuit easily in half with his claw. “So, for your ‘masculine types’, you become wet.”
Keith opened his mouth to argue but when the fingers began thrusting in and out of him it was all he could do to keep his mouth open, warbles of sound leaving his mouth as if he were a songbird singing only for Lance, whose grin could only grow as he gently pushed Keith closer to the cove and sat on a patch of rocks, positioning Keith above his writhing dick, eager for a hot hole to fill. Keith’s mind was foggy, as if he were barely managing to keep his lungs working as he gulped in hot air. “Fuck.” Was all he could really find the words for.
Lance laughed as the tip prodded, and Keith’s eyes widened as he remembered how large it was. “Fuck indeed.”
And with one hard push, Lance shoved his way in. Keith tried to warn Lance, to tell him that he was too big, he wouldn’t fit, but his mouth slammed shut so loudly his teeth clicked and in one glorious moment, Keith was nothing but a warm hole filled to the brim with cock. It didn’t hurt, there was only pleasure, and Keith could feel his body go limp as his eyes rolled back in his head, drool dripping down the side of his mouth as he struggled for breath. His hips twitched wildly with an untouched orgasm as his hands scrabbled for some sort of grip, eventually landing on Lance’s shoulders as he let out silent noises of ecstasy only Lance could hear, toes curling and back arching. He was only vaguely aware Lance was speaking, lips pressed to his sternum and licking the skin there but he couldn’t make out the words as he was sat down on a cock that no human should be able to take.
And it was still going in.
“Can’t-” He could hear his own voice for a moment, a violent moment of clarity as he could feel himself stretching farther and farther, still no end in sight. He tried to right himself, but the water was rough around him and he was helpless to its force. “Too much-”
“No it’s not.” Lance’s voice had gone darker again, and Keith couldn’t stop a whine from leaving his mouth. Sharp teeth were near his ear as his hair was tugged, and the spot behind his ear was nipped at. “You’re still wanting more, still gagging for me.” Another push and more slid in. Keith didn’t have to look to see how his stomach was glowing and bulging slightly from the press, and there still wasn’t any pain. The only pain he really had was the one that laced in his hair, and that was only the good type, Keith had no complaints. He sobbed when finally, finally, it was all inside, and Keith couldn’t stop himself from touching his belly softly, blinking blearily at Lance, who was watching like he was both prey and treasure alike. He opened his mouth and shut it a few times before leaning in and kissing Keith softly, pulling back with a moan as Keith tightened around him. “You’re gonna look so good.” He murmured mostly to himself, but it still caught his attention.
“Look so good whaaaaAAh!” Lance’s hands were on his hips in a brutal grip, lifting him up as if he were nothing but a fleshlight, and Keith could feel himself… needing something. He knew he looked every bit a porn star, judging by the way Lance pinched Keith’s tongue, which was sticking out, and rubbing his thumb over it, a sign for Keith to close his mouth and suck, his breath caught in his nostrils as he messily slurped on the finger, the webbing between a unique taste that tasted like sea salt ice cream. The thumb switched with two fingers, and two became three and pushing down his throat, making him gag but tighten around the dick inside him enough that Lance ripped his fingers out of Keith’s mouth and soon both hands were on Keith’s hips once again, slamming him harder and rougher until Keith was screaming hoarsely with every thrust, vaguely aware he had come for the second time in a row, his dick twitching against his stomach limply as his seed spread in the water. But… he could tell something was missing. Something important, his new instincts told him.
But what?
The answer came when something began pressing at his walls, and he looked up at Lance, who was sweating buckets. “Barbs. To keep you still. Can’t have you moving right now.”
Keith couldn’t bring himself to ask questions, and quickly found out he didn’t need too. Lance’s lower abdomen started glowing with small orbs, roughly the size of apples, and they slowly started to shift towards… Lance’s dick? One disappeared, and Keith felt his eyebrows furrow before rising to his hairline as something round seemed to work it’s way through Lance’s dick, stretching him farther and wider until it finally deposited itself inside of Keith, making his body shake wildly with sensation. Lance seemed to be watching his expressions carefully, thrusting slowed. “Keith, are you okay?”
“Faster.” He could hear himself saying. “Give me more.”
Lance couldn’t stop a predatory growl at that and soon was back to fucking Keith into his next life, leaning down to suck at his left nipple, and then his right. Keith could do little more than writhe as two, then three, then four eggs made their way into him, each one rubbing against his prostate. He could barely hold onto consciousness as a third and final orgasm rushed over him, though he knew some time must have passed, because he was on his back in the sand, Lance looming over him with his dick slowly pulling out, making him moan in loss as something dripped out of his hole (Keith would ask later; hopefully it wasn’t blood). Lance suddenly pointed his dick at Keith and soon Lance was cumming over him. Marking and scenting him, Keith’s mind helpfully supplied to him, managing to make him flush. The substance was blue and glowy too, and some even got into his hair and on his face. So he was dripping on both the outside and inside.
Keith’s fucked out brain couldn’t find it in itself to give that many shits about it.
Lance’s body was suddenly next to his, rubbing over his stomach and kissing his mark, making Keith moan weakly and cock give a feeble twitch. “You look so good with my eggs inside you.” He murmured, and Keith felt a warm feeling out of nowhere make itself known, a feeling of pride and praise from his mate complimenting him.
His mate.
“Mates, huh?” Keith asked softly, slowly coming down from what possibly could be the most mind blowing sex he’d ever have. “Is it always like this?”
“Most times usually. But since you’re human the eggs will disintegrate. But yeah, the sex is always like that.”
Well. One of the most mind blowing.