Chapter Text
Danny watched the water with soul deep desire thrumming in his bones, feeling almost at peace as he watched waves crash against the rocky shore. He felt drawn to it, each frothy wave a siren’s call like the haunting songs Danny crooned when he was in his mer form. It felt impossible to look away, like he was fighting an inevitable thing that could only spell disaster when he turned away.
He needed it. The water. It would keep him safe - it would keep him contained so he couldn’t hurt anyone.
He stumbled a step closer, then another. He needed the water - needed to be submerged like a drowning victim needed air. It felt like the only thing that could fix what was wrong with him. The only place where he could be safe and keep others safe at the same time. He couldn’t go on a violent killing spree and eat his friends and family if he was somewhere in the depths of Gotham’s Bay, with all the drowned mobsters and the shipwrecks from the jagged rocks and the complete lack of life in the murk.
He stepped closer to the shore, the sea salt spray of brackish water cool against his face. He could feel his skin moistening as his skin tingled with the energy of his mer side, his skin threatening to slip easily from human to the smooth scaleless slide of his mer half as he stood in the spray.
He could escape, never get caught by the Monster Investigation Ward or his parents. They didn’t target mer on the shores because they only had jurisdiction in freshwater environments - wild mer were safe since the last living American freshwater mer population had been destroyed by the MIW back in the early 1900’s.
Danny hadn’t known that he wasn’t safe until the MIW was trying to harpoon him and he was forced to flee and shift back to human to escape. He hadn’t known there was a MIW until he’d been turned into one of the monsters they hunted.
He stumbled another small step closer the shore, water inches away from his worn sneakers, and thought about how nice it would be to be a wild mer. He had prey drive instincts, he could hunt for his own food. He could escape from the MIW - who knew his face now, knew that he was part monster. He could keep his friends and family safe from the monstrous thing inside of him, embrace being a horrible beast and shun humanity like some sort of hermit so he never hurt anyone.
He knew very little about mer, but he did know that they were dangerous. His parents studied them, after all, trying to find what made them tick so that they could tear them apart in return for the hundreds of innocent sailors that got dragged to the depths of the sea. He knew that mer created family pods that hunted humans and had a taste for human and mer flesh, often eating innocent boaters and beachgoers and fighting their own species to the death before consuming the bodies of their foes.
They were dangerous, mindless animals that only had the urge to kill and cause inconveniences for humanity by cutting fishing nets and capsizing boats in their waters. Danny was a dangerous, mindless animal. He had caught himself from chasing birds and small animals like some sort of hunting dog, had to fight himself to make sure he didn’t make inhuman sounds that could cause insanity in humans, bit back the urge to bare his growing fangs and inhuman claws and felt the phantom traces of his second pair of arms tucked away in his ribcage when he was above water.
He was a monster. Maybe he should embrace it.
He slid below the waves, clothes tattering and left behind as he slipped into the bay.
—
Danny flitted through the water, chasing after a silvery fish that darted out of his reach for the third time in as many minutes. He let out a sharp click, then bit down on his lip to muffle the following clicks that threatened to leave his throat. He wouldn’t make monster sounds, not unless he had to. He was still a little bit human, even if he was a freak of nature too.
He gave up on chasing the fish, sighing and starting to swim around in search of easier prey. So far he had found a few oysters, some quick silvery fish that he couldn’t seem to catch, and a few crabs that had been the best thing to eat down in the bay so far. He was hungry, but it was only his fifth day in the water and he had hope that he would get better at catching fish soon.
He twirled around himself, long tail knotting slightly before sliding along itself with the help of his scaleless skin, smooth like the glide of fingers through water. He continued swimming, long tail twisting behind him. He hated it, the new length and the squirmy way it moved, knew that it made him less than human, but it was also just so freeing to swim.
He found a boat wreck and set about looking it over, deeper than he had gone before because he had been sticking to the shores out of fear of sharks or predators.
He knew that it was likely that sharks wouldn’t be able to handle Gotham Bay’s pollution, but it still made him feel better to be able to see the shore. Still, this boat was a coast guard cruiser and he was curious.
He had already found the many skeletons and even the one fresh body by the docks with concrete shoes, and he didn’t exactly want to see another human skeleton in the boat, but he did kind of want to see what the inside of a coast guard cruiser looked like. He slipped in through a broken window and poked around, searching through cabinets full of long dead electrical equipment and partially disintegrated paper.
He didn't find a skeleton, thankfully, but he did find a crab which was much nicer. He picked it up and quickly peeled it open from the bottom, ripping off the top shell with the skirt and pulling out its brain to kill it quickly. He didn't like eating things alive, even if the feeling of them squirming in his hands made his instincts sing and his mouth slick with a weird mucous that was probably mer saliva.
He used his blunt claws, which he had scraped down to nubs on the rocky seabed after the third time he'd scratched himself, to pull out the lungs and let them drift to the floor of the cruiser. He didn't know if mer could get sick from eating crab lungs, but he knew humans could and didn't want to risk it.
After divesting the lungs and organs from the center of the crab, he started to pull off the legs and crack them open one at a time, easily pulling out the meat with his partially hooked claws as he held the crabs body with one hand and used another two to crack open shells and pull out the meat.
His fourth was kept wrapped tight around his waist, not wanting to let it drift in case he bumped it with another elbow or accidentally moved it while trying to move his other arms. He didn't have the best control over his new body yet, and liked to use his secondary set of arms as a soothing self hug to keep them from getting in his way or being a nuisance when they moved without him wanting them too.
He finished his crab legs and cracked open the body shell, scooping out meat and licking his dull claws clean even though the chemo receptors on his fingertips still let him taste the slightly sweet, mostly bland crab meat long after he finished eating with his mouth. He dropped the shell to the ground and felt a little better about his outlook, if he could just keep catching crabs and finding oysters.
He slipped out of the coast guard cruiser and looked around, not exactly sure where he was in relation to the shore. He instinctively knew where North was due to his electrical sense, but he had forgotten which way would bring him back to the shore. It was a bay, though, so he could probably pick any direction but East and find his way back to shore.
Curse that silvery fish and getting him all turned around, though, he was thoroughly further into the bay than he'd ever gone before.
He picked a direction - North, since he could feel it tugging on his electrical sense - and set off towards where he thought the shore was.
After a few minutes of swimming, he was relatively certain he'd picked the wrong direction because he only seemed to be going deeper, which was not what he wanted. He nervously chittered, then cut himself off and turned West instead.
Only to pause when something living sparked across his electrical sense, big and foreboding.
It tickled his awareness, looming in the murky waters around him just past where he could see in the dark of night - the only time he felt safe enough to swim considering the boats out during the day - and he felt himself starting to twist his tail further around itself with every stroke, nerves making him want to curl up and loop around himself wildly to disorient the creeping predator.
It had to be a predator, right? What else could be that big in the bay! It was probably a bull shark - they could tolerate higher levels of pollution and had a penchant for being bottom feeders. The trash cans of the ocean, they would probably get a good meal out of eating the bodies of the gangsters by the docks.
Danny sped up slightly, nervous, but the looming thing in the water didn't approach him and instead felt like it was just following behind at the same speed he was moving. Stalking him.
He twirled around and searched the murk for whatever it was again, seeing nothing.
“It's fine, you're not going to get eaten by a shark. You're bigger than most sharks. You're fine.” He mumbled to himself, swimming faster away. The shoreline came into sight and the looming thing against his electrical sense retreated, leaving him alone.
He heaved a deep sigh of relief and curled up under an outcrop of rock by the shore, still kind of hungry and not looking forward to going deeper when the easy to find food ran out.
He watched the water for a long time, and slowly found himself asleep just as the sun started to peek above the horizon, sunlight filtering through the bay's surface.
—
Danny was going insane.
Every time he went deeper, something big crept through the water just out of sight. It was driving him mad, the paranoia and fear and the budding, almost tentative curiosity.
It had been a week, and Danny had gone deeper three times to find food since that first time he found the coast guard cruiser. There was a fatter, slower fish species deeper in the water - some sort of mud dweller like a catfish but bigger and practically fishbait with how easy they were to scoop up and eat.
They tasted horrible, but they were the only food Danny was getting anymore other than the occasional crab and oyster so he returned to the deep over and over again.
The big thing in the water watched him, always lingering just out of his range of sight despite his excellent night vision and the nictating membranes over his eyes that meant he didn't actually need to blink. It let him go when he went back to the shore, and it hadn't tried to eat him, and Danny was getting sick of all the waiting for it to spring from the murk and rip him to ribbons that he was doing while he tried to hunt those fat catfish things.
It didn't follow him back to shore, or burst out of the murk and try to eat him, and he was starting to get really curious as to what it was.
So today he had a plan.
He was going to go find the thing in the water.
A stupid plan, yes, but if he figured out what it was maybe he wouldn't be so scared of going deeper and he could return to the depths for more of those catfish things more often so he wasn't hungry all the time. The sun had set, the stars were hidden by the roiling grey smog over Gotham, and he was ready.
Danny slipped out from under his outcropping and hedged towards deeper waters, trying to build up his confidence. He just needed to see what it was, then he could go back to living like a wild mer and avoiding his problems on the surface like a healthy individual.
The only problem was that he felt kind of warm, like he had contracted some sort of fishy illness and had a fever. It was annoying, his body a little sluggish and his mind a little foggy with some half-ingrained instinct to… he wasn't sure what he wanted to do, exactly, but he wanted to do something. He squirmed in the water and felt his pelvis do weird, squirmy things on the inside too for some reason.
He wasn't sure what to think about that, but it didn't feel like he needed to go to the bathroom and he was decidedly not thinking about if he was going to get organ parasites from eating wild animals so he ignored it, heading out into deeper water.
The big thing found him near instantly, where before it usually took an hour or two to show up. Danny breathed through his mouth, rib gills flickering against his second set of arms where they were clasped around his waist, and tried to hunt the big thing like it had hunted him. He cautiously moved closer, feeling it stay the same maddening distance away, until it seemed to get the fact that he was approaching it - not just swimming in its direction.
He peered through the murk, and after a few short tail swipes he could almost see something looming in the darkness. A dark shape, a smudge that steadily grew more defined until Danny recognized it.
He gasped and instantly began to loop himself, disorientation display making the insides of his pelvis squirm more even as he started to be able to smell them - the other mer in the water.
But that didn't make sense.
How? Why? Mer were violent, unfeeling monsters that ate whatever was in their path - human, mer, or fish. Why had one apparently been stalking him and decidedly not eating him?
Danny watched as the mer drifted backwards a little, still indistinct from the distance but clearly some sort of red and black with a pair of sharp, shark-like fins coming from their hips. They were huge! Easily big enough that Danny had a hard time telling exactly how huge from the distance, but more than big enough that he was sure they could probably bite him in half if they tried.
And they hadn't tried, which was the weird part!
Even now, all they did was watch from a distance. Danny stopped looping because his guts felt even more squirmy now, and he felt even hotter and kind of dazed. He kind of…
He wanted to get closer.
He twisted his tail, not in a distraction loop but in an indecisive swirl that knotted and then slid through itself a few times, before slowly approaching.
Maybe this mer wasn't violent? But why? He had to find out. And be closer.
Everything in him wanted to be closer.
He swam a little closer. The mer drifted back a bit more, but not far enough he wasn't still steadily approaching. They had a shark tail, thick and sturdy like a great white, with black, brown and red patterning.
Their sides, and probably their back and… top…? if they were skimming the surface? Whatever, their sides and probably their back were a deep, inky black, with their forearms and the tips of their fins being a bloody red color that almost blended in with the black. Red was hard to see underwater, Danny knew.
Their underside or their front, from their neck to their tail fin was a rich, leather-like brown. Their face was completely black but for their horns, which were tipped red, and their hair, which had a tiny white streak in the front. Their eyes, when he got close enough, were a human-like yet vibrant sea green with slitted pupils.
They stared at him, silent and still as he approached.
He was so curious, and everything in him wanted to be closer, to get within arms reach and touch. His pelvis squirmed more at the thought, and it almost felt like he was empty in a really weird way that kind of hurt. He guessed he was hungry, seeing as he hadn't eaten in a few days, but that wasn't as important as the mystery of a living mer that somehow wasn't immediately violent.
Danny was only a few tail lengths away now, and holy fuck the mer was huge. Easily big enough to bite a good chunk out of Danny if they wanted, but they simply watched him and seemed unaffected by his curious approach.
Or not. They opened their mouth and made a few sounds that were akin to a soft croon followed by a series of low whistles. Danny startled, looping for a few seconds before he got himself under control.
That wasn't a threat call, he didn't think! Probably!
God this was so nerve-wracking, why did he think this was a good idea? He looked at the mer again, taking in the… well. The muscles. And the overall strength in their body.
They had short hair around their sensor horns, two sharp protrusions from their skull right on their hairline, and looked pretty masculine, but Danny wasn't entirely sure just because their chest was massive and he wasn't going to say that they didn't have tits even if it was probably muscle.
Probably.
It made Danny's guts squirm and he felt himself almost…
No way.
Was he aroused right now? He was still frozen from their noises, but he tensed all over at the familiar warmth in his pelvis that felt a lot like when he got wet as a human.
He looked at the mer again, nervous. They did have a very handsome face, and they were almost exactly his type if his years of reading monster-fucking novels had said anything about him, but this was real life! He didn't want to get fucked by a shark mer, right?
… right?
They clicked at him, whistling again.
It took a second, but he realized that the sounds were words. Language! Mer had language? He thought all his noises were bad, and just noise, not words!
He hesitantly twisted his tail and then swam a little closer, his own chest feeling tight with the urge to make his own noises.
A small peep tumbled from between his lips, and the mer reared back in surprise.
“What?” Came a gruff, human sounding voice. Danny startled, looping for half a second before he got himself under control.
“You talk!” He exclaimed, surprised and delighted and a little flustered because he wasn't sure what he'd said to the handsome, huge mer. God, one of his hands was like two of Danny's, it was honestly making his… mer pussy? It felt like his regular pussy so he was going with that - his mer pussy clench a little from arousal.
“What do you mean ‘you talk’ - of course I talk! You can't offer to - did you not expect me to speak English?” They cut themself off before they could finish what Danny had offered to do, so he wasn't sure what he'd done to make them react like this.
Still! Progress! He was talking to a mer!
“Sorry, sorry! That was really rude, I've just never met another mer. I didn't know you - we - were supposed to be able to speak human languages. I thought I was just really weird.” He admitted, drifting a little closer to look at the clear lines between the brown and the black on the mer's body. The red faded in like a new dawn, blended into the black, but the brown was clearly delineated.
Danny was purely black, with miniscule spots of white that could grow or shrink and change color to camouflage himself. If he looked really closely, he could see that his skin was actually clear except in the white spots, and the white spots expanded to fill the clear part of his skin like a chromatophore on a cephalopod. This mer was solidly colored, so Danny probably was the weird one here.
“You're stupid. What do you mean you've never met another siren?” They asked.
Danny's mer pussy squirmed again at their rough tone and deep voice. He felt his face get warm, but he didn't know if mer could blush so he didn't know if he was blushing or not.
“I just… I don't know. I've never met another mer - siren, sorry. I lived in a lake and all the other freshwater sirens died in like 1924 or something.” He explained, badly.
The mer stared at him, incredulous. Danny peeped at them again.
They instinctively made a soft sound back, then seemed angry by it. “Stop that! You can't offer to let me fuck you if I'm the first siren you've ever met!” They exclaimed.
Danny flushed, gasping and looping twice before swimming back a little bit. “No! I wasn't - You're just! Sorry, sorry, I don't even know what the noises mean, I only know English,” he frantically explained, main set of hands waving as the stranger raised their own huge hands and motioned for him to calm down.
“Hey! Hey, it's okay, are you… are you in preheat? You kind of smell like it, but your scent is also kind of strange so I can't tell for sure.” They asked, a little more calm, a little more soothing.
Danny squirmed, pussy tingling. “What's preheat…? Is that why I feel so hot and stupid?” It had the word heat in it, so maybe this really was a fish disease but it was a normal one.
The mer did something weird with their gills, all of them opening wide and gushing water through them at once. A sigh?
“You've really never met another siren. Okay. Fine. I can give sex ed to a stranger, why not,” they muttered. Danny squirmed and felt the urge to get closer again. He wanted to peep again, too, but he didn't want to make the handsome stranger uncomfortable.
“Heat is your breeding season, means you're ready to fertilize your eggs. Rut is when a mer like me smells a heat scent and gets ready to fertilize the eggs of a mer like yourself. If you don't want to fuck, you shouldn't be out when you're in preheat. A lot of bad sirens will take it as an invitation, even if you don't want it.” They explained.
Danny squirmed more, unable to hold back the peep. The mer sighed.
“You'll also want to jump the bones of any male siren you come across. Come on, let's get you home.” They offered, slowly reaching for him.
He peeped louder and his pussy did something really good and squirmy at that, flexing and feeling suddenly a lot colder than before. He looked down at his body, seeing a weird slit on his pelvis open and pulse as his tail continued to squirm over itself.
The mer went silent for a bit, and Danny shyly peeked up at them before he was pretty sure he was flashing them and that was so embarrassing - but their eyes were locked on his pussy so maybe that wasn't a bad thing.
He peeped again, and they seemingly shook themself out of it.
“Right, right, where do you live? I noticed that you go back to the shore, but I'm a little too big to get closer to the docks so I can only escort you to the shallows.” They explained.
Danny shrugged, hesitantly putting his lower hands over his open pussy. “I don't really live anywhere. There's an outcropping I sleep in during the day, but mostly I swim around and try to hunt. I'm… not very good at it.” He admitted, covering himself and trying not to be embarrassed.
The mer - siren? Siren was the word they used - hummed, a low resonant note that felt like it vibrated Danny's bones. He peeped louder, the sound transforming from a small chirp to a longer warble as he instinctively tried to harmonize.
The siren looked shocked, but shook themself out of it quickly. “Don't- don't try to harmonize with strangers. I'm not going to fuck you, I'm going to take you home. To your outcropping.” They said seriously.
Danny warbled again, unable to help it, then forcefully cleared his throat. “Right. Right. Sorry, I don't mean to… uhm. I don't know what I'm doing, but I don't mean to do it. Is it really that bad for me to be out while I'm in heat?” He asked.
The siren sighed, but started to swim around him instead of picking a direction to go. It felt like being circled by a - well, a shark, and seeing their red tipped dorsal fin and strong tail cut through the water around him made his pussy do more embarrassing squirmy things.
“This is a bad place, sweetheart. Bad sirens live here, and they wouldn't hesitate to fuck you if you wanted it or not. You're lucky I'm not an asshole.” They said. Danny squirmed.
“You could be a little meaner. Maybe. If you wanted to.” He said without thinking, then squirmed harder as his tail knotted over itself and he had to fight to keep from sinking because of how bunched up he was.
The siren groaned, circling him tighter and making his pussy throb as they started to smell really good, musky and sharp like cologne. “You don't mean that, I'm not the kind of siren you'd want to fuck.” They said.
Danny tried to get his squirming under control, but the problem was that they really were apparently the kind of siren he wanted to fuck. He absently wondered if sirens even had dicks, since they were fish, and if this one was proportional.
“I've seen other sirens on like, the internet. I didn't want to… fuck… with those ones. But you don't have to if you don't want to!” He hurried to reassure, suddenly feeling kind of bad. Was he pressuring them? They were really his type though, and he was feeling so needy and hot and empty.
They groaned again and he warbled back, white spots flickering a soft, almost romantic pink as his desire spiked from the sound.
“You're going to kill me. You're not just sayin’ that shit either, you really do want me?” They asked. Danny hummed a wanton note, or at least he thought it was, and felt his pussy throb with desire.
“Please? You're really hot, and you also don't want to eat me which is nice, and you tried to be a gentleman but I'm also really horny and I've never… with another siren…” he trailed off, tail knotting together again as he hummed another wanton note.
The siren finally stopped circling and reached for him, wicked claws making Danny think of being ravished like a maiden in a werewolf erotica novel. God that would be so nice.
Instead of scratching him, they took his upper arm biceps in their own upper arm set of hands and started to tug him deeper, sea green eyes blazing bright in the dark water. Danny chirp-warbled and then gave a low croon, almost like whalesong, that got him a deep melodic hum in return.
“Okay, okay, we can go back to my nest then. You're sure…?” They asked again.
Danny whined, this time begging, and got a soft curse and a pick up in their speed in return. He kept his lower hands covering his throbbing pussy, but swam with the siren deeper into the bay.
“Why did you live in a lake, anyway, pipsqueak? You're obviously a saltwater eel, no scales. Didn't that hurt you?” They asked, tugging him further and further into the murk. He tried not to be scared of the deeper water, and considering how big his new companion was it was likely no one would try anything, but he still felt uneasy as the surface stopped being distinct and all he could see was the murk above them.
“I uh. I was born there? I didn't think I could leave, but there was this group of monster hunters that kept trying to get me so I had to go anyway or I probably would have died. They're why the freshwater sirens are all dead.” He explained, a little distracted by just how big they were and how nice they smelled.
They paused. “... we'll come back to that later. Why did you come to Gotham Bay?” They asked, tugging him deeper again.
He hummed, then warbled an aroused sound when their tail brushed against his as his tail squirmed. It felt so good. He wanted to wrap his tail around them and do… something. Fish sex, probably.
“A-ah, well, it was the closest shoreline I could get to that wasn't fresh water. The great lakes are under the MIW's jurisdiction, even if they're deep enough to hide in. I don't… I've never been this deep before, actually. It's a little scary.” He admitted, trying not to be a baby but nervous all the same as they passed old shipwrecks and he started to feel other living things buzzing against his electrical sense.
The siren click-hummed at him, softly, as if they were reassuring him. It helped, a little.
“They don't have jurisdiction in the ocean or salt water because of an old treaty the American government made with the king of Atlantis, so they can't get me here.” He continued to explain.
They came to a large cliff, with a big cave opening deep into the rocks. Big enough for a siren like his companion and then some, which made him almost feel awe over the thought of an even bigger siren. They were huge! Easily twice Danny's size and more, their torso was easily so broad that Danny would probably struggle to reach from one shoulder to the opposite shoulder even if he stretched his arms as wide as they could go.
“Okay, that's good to know. You'll be safe here, okay? This bay is my territory and I don't let hunters or poachers come close.” They stated clearly possessive of their territory but somehow willing to let Danny encroach? Weird. Good, but weird.
“Sorry for being in your territory without asking,” he mumbled, arousal dying a little bit still lingering enough to be distracting. “I didn't know sirens had territory if they didn't have a pod.” He admitted, thinking back to his parents' research.
They hummed. “Not that kind of territory. And it's pack, not pod. I patrol my side of Gotham Bay and keep any humans from thinking they can fuck with the siren population here, and I also keep any sirens from being dumbasses or hurting each other.” They explained, tugging Danny into the large cave and through a long set of winding tunnels.
“My pack also patrols in different parts of the bay, we all have our own little section. It's still not safe for you to live near the shore, even just to sleep, so I'll help you find somewhere nice to stay once we get you through your cycle.” They mentioned offhandedly, tugging him into a side tunnel that opened into a relatively well lit room.
Bioluminescent algae fluttered across the walls, coming alive as the two of them entered and the water currents stirred up by their movements woke up the lights. It was a soft blue-green that cast rippling shadows across the room like light striations through the surface to the seabed.
Danny stared at it in shock, then realized that of course sirens didn't have electricity and still found a way to keep themselves out of the dark.
“That's nice, how do…” his guts squirmed and he felt more aroused again when he saw what was clearly the nest - a big rock with a smooth divot in the middle to turn it into a large bowl, filled with more algae and some seaweed of some kind that looked actually pretty comfortable instead of slimy and gross how he thought most things underwater would be.
He gulped down a mouthful of water, swallowing thickly, and hummed a short two note tone followed by a peep, before finding his human voice again.
“H- how do uh, how do we get me through my cycle? I know how human sex works, but I'm guessing siren sex is different.” He mumbled, staring at the nest.
It looked perfect to lounge in for months on end, and he wanted to curl up in the middle and hibernate a little bit despite not being tired. He was drawn to it.
The stranger chuffed, an amused sound. “First,” they said, drawing him closer to the nest. “We would get comfortable. Touching, foreplay, that sort of thing.” They explained, pulling him down on top of them into the nest.
He purred, the hands covering his pussy coming up to grasp at their waist - which was more of a large hug than a sexy grab but still - and let his primary arms come up to trace their forearms where they were holding his biceps.
They hummed, a pleased note.
“See? You're getting it just fine, sweetheart. Look at you, such a pretty little thing displaying your slit for me,” they rumbled, voice harmonizing with the purr that kicked up in their chest.
Danny's tail squirmed, brushing against theirs and instinctively starting to wind around it. He wanted to be tangled around them, for some reason, and he had a feeling that was just how fish sex worked so he didn't fight it.
“Next, you lock together - just like that, baby, you're doing so good -” they praised when he finished winding his tail around them, significantly lower on their body than where he kind of wanted to be face to face. His head was more around their lower ribs and the very bottom of their pecs, which was also nice so he didn't complain.
“... then what?” He asked, tentatively squirming and gripping them tighter with his tail. His pussy - or slit, as they called it - throbbed where it rubbed against their rough sharkskin scales.
They crooned, purring louder. Danny crooned back, trying to harmonize again.
“Then, sweet thing, I release my claspers -” there was the sensation of something opening against his slit, and then something massive pushing out and sliding to either side of his tail. He shuddered, looking down to see two giant cocks coming from their own open slit thing.
Each one was about the size of Danny's forearm, easily a foot long - or more - and thicker than his wrist. He whimpered, a needy sound, and his slit felt like it gushed despite being already wet from the water around them.
His new lover chuffed, amused. “You like that? You can have one, if you still want it.” They teased.
Danny looked back up at their face, squirming again as his slit throbbed with desire. “One?” He asked. “Is… does it not feel good for you to use both?” He wondered, not sure why else they would stick to just one of their beautiful cocks at a time. Claspers. Whatever.
He looked back down at them, taking in the pretty pink flesh and the swollen tips. They looked a lot like human dicks, just huge and there being two of them.
His lover paused their purring. “You… want both?” They asked, almost nervous to even offer.
Danny trilled, a three note song of acceptance, before realizing explaining would probably be better than singing.
“Not if it hurts you or makes you uncomfortable!” He rushed to explain. “But. Uhm. Yes, if they'll fit. Both?” He asked, making a wanton purr.
They instantly made a long, low song note, like a blue whale, followed by a serious of clicking chitters before seemingly catching themself and shuddering in the grip of his tail.
“We can. We can do that. Yes.” They breathed out, gills fluttering. Danny flushed.
Was that kinky? Was he being really weird and kinky? Sirens had two dicks, surely it wasn't super weird to want both of them inside of him at once…?
Still, they had said yes. Seemed excited about it too, if the way their claspers were throbbing against him. He squirmed and tried to pull back so he could notch them both at his entrance, wanting more than anything.
It would probably hurt, but Danny kind of liked a little pain anyway. Their hands tightened on his biceps, and their second pair fell to his hips to keep him still.
“Patience,” they chided. “One at a time.”
He pouted, but let them move his hips and catch one tip against his pussy. He shut his eyes and sang a high pitched note that made his throat hurt a little, followed by longer warbling song that felt a little haunting to Danny's somewhat human mind.
This was the kind of song that drove sailors mad.
Really? Siren sex was what did it? He giggled slightly, and relaxed his pussy as they started to slowly press inside.
The tip spread him open, making him sing louder, a thrumming cry that made his insides squirm with desire, until they popped into him and his entire body locked up like a steel trap.
His tail tensed around them, hands gripping tightly, head falling back as his mouth fell open and he sang a sharp burst of whalesong, deep and resonant. His lover let out their own song, an even deeper register that thrummed through Danny's bones.
He harmonized with it instinctively, singing along as he was speared, inch by inch, down onto their clasper.
His slit fluttered, clenching rhythmically and making him sing louder for a few short notes before falling back into the normal - or, he thought it was normal - range. His lover purred and sang back as his pelvis hit the middle of their clasper, the tip pressing back against what he was pretty sure was his cervix as they held him for a long moment, crooning a haunting song that made Danny want to cream himself on the spot.
Finally, after about twenty more seconds of being frozen, he shuddered and stopped locking up and clenched down on them purposefully. Their song got louder and deeper for half a second, then smoothed out again. They pulled his hips away from theirs, notching their second clasper against his slit and making him tremble with anticipation as his song swelled into a sweet ringing trill that he imagined meant yes yes yes please.
They popped the second tip inside and Danny locked up again, singing strong and loud with warbling, wanton notes as his lover pressed back inside. It felt so good, every inch spreading him open like a flower blooming in a soft spring rain, stretching him with surprisingly little pain.
Oh he was full, almost to his limit, but it didn't hurt - it was more like that one time he had spent an hour stretching himself to fit his fist inside except way more intense. Sparks of pleasure crawled up from his slit and settled low in his tummy, and they were soon pressed to the back of his slit again except this time they didn't stop.
Danny felt himself stretch, then felt something inside of him give way as they sheathed both claspers to the hilt inside of him. His song stuttered, feeling like he had been cored out and stuffed full at the same time as his slit clamped down tight and he felt a wave of pleasure wash over him.
He couldn't help it, he orgasmed with a long, drawn out note that felt like a scream of pleasure, head thrown back to bare his throat as his gills fluttered and he locked up again.
His lover kept singing, though when he looked at their face when he regained control of his limbs they were obviously smug. He was sure that if they stopped singing they would be teasing him. He didn't care, it felt amazing, whatever they were doing to get so deep that they were making him feel more full than he'd ever been before, slit throbbing with arousal and clenching down on them as he instinctively tried to milk their claspers.
They stayed like that for a long moment, until his gills stopped fluttering, before using their hands on his hips to drag him off their claspers and then pull him back down - staying deep enough to never leave the secret second slit inside of Danny that they had breached. He sang and sang and sang, each note a moan or gasp that kept up a litany of yes yes yes in his trilling voice.
They sang back, using his body like a cocksleeve even as their grip got tighter and their song got deeper and more resonant. It shook through his bones, making his guts feel like jelly as they were rearranged. Danny let go with one hand to press against the full feeling as they bottomed out again, gasping at the clear feeling of something pushing against his sensitive palm and distending his stomach.
He looked down to see a clear bump through his tummy, right above his belly button from how deep they were. He sang louder, please please please with an undernote of oh god oh god yes as his song moaned out his words for him. His lover's grip on his hips flexed, tightening before releasing then tightening again.
Their songs resonated in the cave, and Danny felt a second orgasm build quickly with how stuffed and sensitive he was, still coming off the tail end of his first. He sang louder, tail tightening around them as his slit throbbed and pulsed and felt so so good fuck.
He sobbed his song through a wailing cry as his second orgasm crashed through him, pleasure squirming in his gut as he felt something stretch his slit even wider at the entrance. He continued singing, and his lover continued to use him even as their purr transformed into a growl beneath their deep song.
He continued to wail his pleasure, aftershocks zinging from his slit to his tummy and making his tail squirm and tense around his lover until the wider press of something punched through his slit and locked, swelling just inside of his entrance and making him cum so hard his vision went white and his ears rang with tinnitus, slit milking the - oh god the knots.
He cried, sobbing his song out with sharp warbles of pleasure as his mate's song hit a crescendo and fell into a long, loud note that made his horns throb and his bones ache. Danny scrambled weakly at their hips and arms, even as something hot started to fill him up from within. The bump under his hand expanded, slightly, and his song cut off with a sob of overstimulation.
His lover instantly stopped singing, one hand gently taking his chin and making him look at their suddenly sharp eyes. “Hey, hey! Does it hurt? Are you okay?” They asked, slightly frantic.
He shook his head and sobbed again as the bump continued to get ever so slightly larger.
“Talk to me, sweetheart, tell me what's wrong,” they demanded, even as their claspers flexed inside of him and he clenched down around them in response.
He gulped water, breathing heavily through his gills until the overstimulation smoothed out into a pleasant, warm ache in his slit and tummy.
“I- s- sorry I was just overstimulated-” he tried to explain, somewhat dazed. “S’ so good, oh my god it feels so good,” he slurred, head lolling as he milked the knots inside of him.
He was so full. He wanted to be stuffed with his lover's knots until the end of time, never let off of them again.
Said lover gave a relieved sigh.
“And you're not hurt? Two knots is a lot for your first time, I shouldn't have let myself- we should have stuck with one.” They said anxiously.
Danny grumbled at them.
“Two knots is perfect and anyone who says otherwise is a pissbaby loser that wouldn't know a good thing if it was a sexy shark siren with beautiful tits right in front of them.” He mumbled, voice a little sore from singing.
His lover chuffed, hesitantly amused. “Tits?” They asked.
Danny hummed, resonant and song-like for half a second. “You have the best tits I've ever seen. Ten outta ten.” To prove his point he reached up with a primary hand, feeling them let go of his bicep as he groped one of their fantastic tits. He groaned, pleased by the firmness and the slight squish.
“The best. Oh my god. You're like a dream come true,” he said nonsensically.
They chuffed again, more confident. “You're cute, pipsqueak. You always get so knot drunk or - ah, you've never had a knot actually, you wouldn't know, would you?” They asked, letting go of his other bicep and holding him close in a warm hug. Comfortable.
He rested his head on their sternum and sighed, pleased when the bump under his hand stopped growing and the full feeling hit its peak. “I would one hundred percent get knot drunk again if it meant more amazing sex,” he claimed.
“I would do pretty much anything for more amazing sex. Siren sex is so much better than human sex, there's no competition.” He continued.
His lover tensed a little, then seemingly forcefully relaxed. “Yeah? When did you have human sex, little thing?” They asked.
He shrugged. “When I was like… fifteen? My best friends and I were tired of being virgins and decided to go the friends with benefits route. It didn't last long, they both got together and I stopped sleeping with them because I didn't want to get in the way of their relationship. It was nice, but not as nice as this.” He looked up at their face, the long pointed ears twitching and horns sharp against the green blue algae light.
“That's not important though, I just realized that we had sex but I don't know your name. I'm Danny, by the way.” He nuzzled into their chest, a little too short to reach their tits but still happily pressed torso to stomach where their six pack was delightfully tensing beneath him with every throb of their claspers.
“... Jason.” They said. That was a masculine name, and they had two dicks, but he still didn't want to assume so Danny paused.
“My pronouns are he/him. What are yours?” He asked, shyly. He knew that he had a siren pussy, not a set of cocks, but he hoped that they wouldn't be mean to him.
Jason pet along his spine with the backs of their fingers, trailing down the slight raised ‘fin’ of his spine that went all the way to the tip of his tail like a paddle because he was an eel. “He/him as well. You're cute for asking, after getting speared open on my knots.” They chuffed.
Danny flushed, or did the siren equivalent. His face was hot. “It's rude to assume!” He tried to keep his cool factor. Not that he had any, since apparently Jason thought he was cute.
He wasn't cute! He was a monster!
Or. Well. A siren. He was getting the feeling that sirens weren't actually monsters and his parents and the MIW had been wrong.
“I guess you're right. I did assume you were a girl, and I was wrong, so that's on me.” Jason admitted, continuing to pet him as his claspers throbbed a few more times before falling still. Danny was so full, it felt amazing.
He sighed, happily nuzzling his lover. “You said… something about eggs? Am I gonna lay eggs now?” He asked, tentative.
Jason chuffed. “You've never laid before? You don't have to let them hatch, don't worry, but in about a month you'll probably have a few fertilized eggs. One to five, maybe more, you just have to cut them open if you don't want guppies.” He explained.
Danny hummed, then yawned, glad he wasn't going to be a parent when he was freshly eighteen. “And they… it won't hurt them? They're not babies yet, right?” He asked.
Jason chuffed again. He did that a lot, the bastard. Amused at Danny's lack of siren knowledge. “No, sweetheart. They're just eggs, it's like with… uh. Birds? The egg comes out when it's done developing the shell, but the guppy doesn't start growing until after it's laid.”
Danny shuddered. Bird eggs. Siren eggs. Danny was going to lay eggs. “Will it hurt?” He asked.
Jason made a soft croon. “No, sweetheart. They're soft shelled, jelly like. About the size of your fist. Smaller than my knots, I promise.”
Danny breathed a sigh of relief. He would probably barely look pregnant if the eggs were so small and there were only a few of them! He peeked up at Jason and found the other wearing a fond expression.
He yawned, caught himself, and then yawned again. Jason looked even more fond.
“Go to sleep, little thing. I'll be here when you wake up.” He crooned, running his pointer finger knuckle on Danny's cheek. Danny sighed and nuzzled into his chest again, letting his eyes slip closed.
“We shoul’ do this ‘gain…” he mumbled. Jason chuffed.
“Sure thing, sweetheart. After you sleep.” He said easily. Danny sighed happily.
“Promise?” He asked.
“I promise,” Jason said.
Danny slipped into unconsciousness easily, after that.