The New Sirens [A Mermaid TG Story] - Part 1

Commissioned by cooloo

Forty years after Charlie’s Sirens, a new vaccine allows merfolk to switch between genders more easily. Sam is secretly in love with his two roommates and when they start dating without him, he finds his gender in flux as his hidden desires are brought to the surface. 

Part 1

Sam leaned in close to the screen, watching the news report closely. The anchor was a mermaid who smiled just a little too widely to be genuine.

“Good evening, everyone. Our top story tonight: Twenty years ago today, a breakthrough was made in both biological science and gender equality when a pioneering former human turned mermaid, Charlie Kingston, developed a revolutionary drug that allowed mermaids to transition between genders with ease.”

“For centuries, merfolk have lived in a society with a minority male population, with three mermaids for every man. Thanks to our inherited metamorphic gene, this ratio was always maintained, with males becoming female and vice versa based on the proximity of other merfolk. With the change being hormonal, involuntary, and often unpredictable, many had to face life in a body that was not their true self. But with the invention of a vaccine, merfolk could now control when and how they shifted, offering a new era of personal freedom.”

“Tonight, we’re joined by Charlie, the biologist who made all of this possible. Thank you for being with us today, Charlie.”

Sam smiled as the camera panned over to the older merman. He had the same familiar warm smile on his face that had drawn him to biology. Professor Kingston spent most of his time teaching these days, rather than researching, and Sam couldn't help but feel special to be one of his students. 

"It’s an honour to be here; thank you for having me."

"It’s hard to believe it’s been twenty years since the introduction of your groundbreaking drug. Can you take us back to that moment and tell us what motivated you to create this solution?"

"As you know, back in my youth, I was human and came to Atlantis on exchange. Three of my friends, all men, were transformed into women as a result of the metamorphic gene and the process was...not particularly smooth. Even after deciding she liked her life as a mermaid, one of my wives, Marina, still struggled with her appearance and gender identity for a time afterwards. I wanted to make sure the next generation didn't have that problem."

"And now, 40 years later, the vaccine is distributed at birth. Do you think there’s been a cultural shift in how mermaids perceive their gender identity since the vaccine was introduced?"

"Absolutely. There’s been a huge shift toward understanding that gender isn’t just about biology—it’s about who you are inside and having the freedom to express that. Before the vaccine, many merfolk felt disconnected from their true selves because their shifts weren’t under their control. Now, people are able to experience what it’s like to be another gender. Of course, the metamorphic gene can never be truly controlled; heightened emotions and hormones can still trigger involuntary changes, but at least for the majority of merfolk—”

The screen suddenly went black, and Sam blinked in confusion.

“Why are you watching some report on ancient history?” Asked Devon with a smirk, laying a hand over his roommate’s shoulder. “If you want to talk to Professor Kingston, you can do it in a few minutes when we have class.”

Sam rolled his eyes.

“It’s not ancient history, Devon, it wasn't even half a century ago.”

“You say that like fifty years isn’t an age.”

“You should be thankful,” Sam said as he swam over to his desk. “If it weren't for Professor Kingston, you wouldn’t be male right now.”

“I’ve been male since I was thirteen, dude. And if it weren't for the fact that the metamorphic gene doesn't kick in till adolescence, I’d have been one before that.”

“Only thanks to Professor Kingston’s research.”

“Yeah, I know. But that doesn't mean I have to watch every report about it. They do a special on the vaccine every year, we all know about it already. I just don’t get what you’re so into learning the same information over and over.”

Sam sighed. He didn't expect Devon to understand. He may have been born female, but he sometimes had the emotional depth of a teaspoon. It should have been the other way around really, Sam had been born male and always stayed that way, Devon was the one who shifted from female to male as soon as he had the chance. He should be the one who felt thankful for the vaccine, not Sam. Yet here they were. 

“Come on, I need your help, which is better?” Devon asked, holding out two bracelets, one made of interlocking rainbow coral the other classic pearls. 

“Better for what? Your complexion?” Sam teased, and Devon rolled his eyes. 

“For Alice.”

Sam’s mood soured immediately.  A relationship bracelet: the first step to starting a pod with somebody. Ideally, the mermaid would expand this bracelet in time and move it to her tail as a wedding band. 

“Oh…” He looked over the two gifts. The pearls were old-fashioned and classic, but he knew how much Alice hated them. She said they made her feel like an old fish. 

“The pearls, for sure.” He said, not making eye contact. “Old fashioned, but they are traditional for a reason…are you sure about this? It might make things…weird.”

Sam had been friends with both Devon and Alice since they were children. Now, they were all roommates in college, just like Sam had always hoped, but their actual relationship wasn’t what Sam had imagined. 

In childhood, he’d had a crush on Alice and Devon and spent days daydreaming about being a pod one day, with him as their male. It didn’t matter that Devon also had a thing for Alice, they were merfolk, after all, the female members of a pod would often indulge one another, especially if their male was away. Sam didn't mind his two females being together, so long as they were a pod. But then Devon announced he was male, shifted bodies and that was that. Sam expected his crush to fade over time, but it never did. Neither did Devon’s feelings for Alice. 

“Great, thanks, man!” Devon said, totally oblivious to Sam’s feelings.

Guilt swirled in Sam’s stomach as he watched Devon put the coral bracelet away. He knew Alice would like that one more, it felt wrong to lie to his friend but maybe that was a sign. If Devon couldn’t even pick out a relationship bracelet he knew Alice would like, maybe he shouldn’t be starting a pod with her. Sam knew they both so well; he’d be such a good lead for their pod if they’d open their eyes to see it. Or if he were brave enough to voice the idea. 

“Devon! Sam! Are you ready to go?”

The voice was warm, musical and sent a shiver down both mermen’s spines. Alice floated into the room slowly, her golden tail glinting in the sun and blonde hair flowing slowly behind her. Devon quickly hid the bracelet behind his back and grinned. 

“Yup! Don’t want to be late! We were just talking about professor Kingston! Today is the forties anniversary of his miracle drug, did you know that?”

“Really? I shouldn’t be surprised, of course you would know that, Devon. That’s amazing, I wonder if he’ll talk about it in class.”

Sam pressed his lips into a thin line, watching them both turn pink in the cheeks while looking at each other. His eyes slid over to the bag where Devon was stuffing both bracelets; all he could think about was how good the rainbow one would look against Alice’s golden scales one day. 

Devon grabbed his bag and swam over, curling over Alice playfully so that their tails almost brushed, green meeting gold, and for the first time, Sam saw how good they looked together and felt sick with jealousy. You’d never guess that Devon had been born female, his male form was as masculine as they come, with dark olive skin, an athletic build and dark hair that complimented his dark green scales and eyes. While Alice was a golden girl through and through, with blonde hair, gold scales and the curves mermaids were known for. Sam, on the other hand, felt so plain. Short brown hair, a thin build and dark red scales. He wasn't ugly by any stretch of the imagination, but he certainly didn't look like the sort of male who would lead a pod traditionally. 

“Sam? Are you okay?” Alice asked. “You look a little green around the gills.”

“I’m fine!” He lied. “Just uh, thinking about that…essay we have. I totally forgot to finish it, so now Professor Kingston is going to be angry.”

“We had an essay!?” Devon yelled, and Alice rolled her eyes and patted him on the shoulder fondly. “Don’t worry, I am sure the professor can give you an extension if you ask. You too, Sam. Now let’s go, we’re upperclassmen now, we need to set a good example, and that means not being late.”

She reached out and grabbed his hand, pulling him into their little huddle as they swam out of the window and down towards the rest of the university campus. Atlantis University hadn’t changed much since its inception but the merfolk who attended it had. Small pods swam past with smiles, as did other groups of friends like them. He watched as the others gave one pod, all marked with matching bracelets, a wide berth. A single female, with two males. 

Despite all the changes that had come with the vaccine, pods were mostly still created around a single male. Despite the vaccine, old habits died hard. The gender ratio was slowly growing more even, but there were still far more mermaids than men. With females taking up almost seventy percent of the population. To see a pod with two males while not against any law, was still odd. Sam imagined a world where Devon is still female, where he and Alice wear matching bracelets with him and follow his lead. The daydream just made him sigh sadly. The truth was, he didn't have the backbone to lead a pod. If he did, he would have asked Alice first rather than pinning all this time while Devon took the initiative. 

“It’s fine, she won’t say yes.” He whispered, trying to convince himself. 

Alice had never shown any favour towards either of them. She would turn Devon down. It would be awkward for a while; he and Devon would go out drinking and wallow in his sorrow for a bit, and then they could all go back to being friends and roommates. Then Sam could at least pretend they were a pod and that he wasn’t getting left behind. 

He was glad when they got to class and had something to distract them. The interview on TV had clearly been pre recorded because Professor Kingston was already at the board, writing out the day's lesson plan and greeting students. Sam tried to pay attention, but it was impossible. His mind kept sliding to the bracelet in Devon’s bag and what it could mean. For a brief moment, he considered taking it; without the bracelet, his friend would probably lose his nerve, but he quickly dismissed it. He wasn’t a thief, and he didn’t actually want his friends to be upset. He just…didn’t want things to change. 

“Hey, what’s going on?” Alice whispered, elearning over with a look of concern. “This isn’t just essay nerves.”

“What are you talking about? I’m fine.”

“Sam…I have known you since we were tiny, I know when you’re upset. Why are you keeping it a secret.”

Sam swallowed; damn her, damn her and her caring eyes and comforting voice. 

“I…”

The sound of Professor Kingston clearing his throat made them both freeze and turn back to the front, where the older merman was fixing them with an expectant look. Sam gave him a sheepish smile and sunk lower into his chair as the lecture continued. He watched the clock, it felt like a ticking time bomb. Normally, he was willing classes to speed up, but today he wanted nothing more than for things to go slower. When the bell finally rang, he shot up out of his seat in shock, making the crowd giggle around him. He turned to Devon for sympathy, but he bowed his head low, whispering to Alice as they both made their way out of the room. Sam felt his stomach sink; a quiet dread slowly chilled his blood. She wouldn’t accept his offer. She couldn’t. 

“Trouble with you pod?”

“Professor!” Sam spun around to see the older merman looking at him with a wry smile. “Uh, no sir, we’re not, the three of us I mean, we’re not…we don't date.”

“Could have fooled me. You all have the distinct look of nervous young people in love.”

“Well, we’re not,” Sam said sourly. “Besides, Devon is a male, we can't have two males in a pod.”

“I’ll admit, having more than one male is rare. Mermen are naturally territorial and protective of their families, which isn't conducive to sharing. But, the times are changing…and males don't have to be macho like they used to be.” Professor Kingston smiled softly. 

Sam blushed; years of marriage to a psychologist had made Professor Kingston good at reading people, maybe a little too good for Sam’s taste. He hunched his shoulders together and tried his best to sound defiant.

“I know that. I could lead a pod if I wanted to.”

“Of course you could.”

Charlie wasn’t being sarcastic; his voice was warm and supportive, and somehow, that only made Sam feel worse. He eyed the older mermaid and, for the first time, felt irritation spike inside him; if Charlie hadn’t created that vaccine, Devon would probably still be female along with Alice; they would have become a traditional pod naturally over time. Or at least, it would have been more likely, and he wouldn’t have had to worry about these confusing feelings for another male. 

“Thanks for the lecture.” Sam said quietly, “I’d better get going; my…roommates are waiting.”

He swam away quickly before Charlie could say more. Sam bit his lip angrily as he swam out into the courtyard; who did that old guy think he was anyway? He may have made that miracle vaccine, but who cares? It wasn’t even foolproof! And he didn't know Sam; he was just his professor, and it wasn't like he asked the guy for advice! He looked around for Devon and Alice, but they were nowhere to be found. Instead, everywhere he looked, the universe seemed to be taunting him with happy pods and couples swimming to and fro, taunting him with their happy smiles. 

“This is stupid, Sam.” He sighed to himself. “You’re getting worked up over nothing. Don’t let it get you all twisted.”

He waited for a while, trying to convince himself that Alice and Devon would come looking for him before their next class, but they didn’t. Eventually, he was forced to go on his own, quietly reminding himself that they had different minors him and probably just had to get across campus. So what if they were usually all left together? It didn’t mean anything.  

By the time classes ended for the day, he had almost managed to forget his sour mood only for it to return the moment he opened their apartment door. Alice swam right up to him, face beaming and a shiny new pearl bracelet on her wrist; the sight made Sam’s heart sink.

“Sam! There you are! You disappeared after Professor Kingston’s lecture!”

“No, I didn’t.” He snapped. “You both left without me.”

“Oh, sorry.” She said without sounding sorry at all. “Devon said he had something to ask me and…look!”

She thrust the pearls under his nose and Sam resisted the urge to sneer at them. 

“We’re officially dating! Isn’t it wonderful?”

“I did it, man!” Devon announced, appearing from behind Alice. “Thanks for your help.”

“Devon told me you’ve been his sounding board.” Alice beamed. “I can't believe I didn't notice the two of you scheming!”

Sam could hear the blood rushing in his ears. He wanted so badly to be angry but knew he couldn’t be. Alice and Devon hadn't done anything wrong, not really. This was his problem to get over. He forced a smile onto his face.

“That’s great! I am so glad you said yes!” He lied. “I was worried about things getting awkward between us all if you didn’t.”

Alice giggled, and Devon put his arm around her shoulder. He was smiling ear to ear; they both looked so happy. It should have made Sam happy, too, seeing the two people he cared about most in the world so happy. But it was a unique kind of torture to see two people he had feelings for happy with each other. 

“Are you doing anything to celebrate?” He asked, not sure how else to continue the conversation.

“Dinner, of course!” Devon grinned. “I booked us somewhere special. It’s not every day you start a pod.”

“A pod! Do you have another mermaid in mind already?” Alice teased, elbowing him in the ribs.

They both laughed, and Sam felt a strange ache form in his chest and an emotion he couldn't identify started to build within him. 

“Oh shoot, we’re going to be late!” Devon cried. “So glad you came back, we didn't want to leave without telling you.”

Sam just smiled and nodded, moving aside to let them go. 

Devon raced off but Alice hung back, just for a moment and placed a hand on his shoulder.

“I know this is a bit awkward.” She said, “I promise we won’t make you feel like a third wheel, rooming with a couple.”

“Thanks.” Sam croaked. “I hope you enjoy your…date.”

He almost choked on the last word; if Alice noticed, she didn't say anything. Just gave him a sympathetic smile and hurried on after Devon, leaving Sam alone in their apartment. For a moment, he was glad not to have to force that fake smile on his face, but then a blanket of unbearable loneliness seemed to settle over him. His two best friends were dating and left him alone. The apartment had never felt so cold and empty, and he settled in for a long night of feeling sorry for himself. 

~

Sam rolled over in his bed, feeling the seaweed blanket float up slightly as another body shifted next to him. A tail brushed against his own, bringing a soft smile to his face. His eyes fluttered open, and he saw green eyes smiling back at him. It was Devon, and he had the soft look of love on his face that made Sam’s stomach twist. A hand raked through his hair, and Sam realised something was different. He could feel locks flowing down his back, soft and wavy, as the fingers raked through them. He turned, and there was Alice, smiling at him with that same adoring look in her eyes that took his breath away. 

His two best friends snuggled closer, hands slowly roaming over his body. It was like those sleepy Sundays that always happened in romance stories, where lovers woke up entwined and slowly rose to greet the day with tender sex. His cock throbbed inside its sheath, but…it felt different. He looked down at his tail and saw familiar red scales, but as the patch at the front receded, no cock emerged. Instead, it was a pussy, wet and ready as Devon slid closer and Alice massaged his shoulders. 

A shiver of want ran through him as Devon moved closer until he felt his folds start to part, welcoming the cock inside with a deep moan. 

Sam woke with a start; his skin was hot, and his blankets were in disarray as he desperately tried to catch his breath. His chest was heaving as his breathing tried to even out. What sort of dream was that? 

“Oh my God, Sam. What is wrong with you.” He whispered, “You can't go dreaming about your friends like that!”

His breathing calmed, and his heart rate slowed, but something still felt wrong. His chest felt heavy, much heavier than it should have been. He looked down and felt his heart stop altogether for a moment. A small set of breasts was on his chest, only B cups, but still. Sam had never shifted genders before, but now he knew why that dream felt so real. His cock was gone, as was his square build; replaced with soft curves and hair that reached his shoulders. 

“O-Oh God.” 

His metamorphic gene! Thanks to all his buried feelings bubbling to the surface yesterday, it must have been activated! Damn Devon, if he hadn't asked Alice out, Sam could have just gone on ignoring those confusing feelings for both his roommates. Now, he was turning into a mermaid! A less feminine looking mermaid than most at least, but still. 

“No.” Sam grit his teeth. “I am not doing this.”

Thanks to the vaccine, he knew it was possible to will himself back to being a man if he tried hard enough. He’d been given it at birth like all other merfolk his age, but up until now, he’d never needed it. Sam focused hard on his own masculinity, trying to will the changes to revert. Just as he was about to give up, he felt a subtle shift in his hips as they began to narrow, and he breathed a sigh of relief. It was a bit disconcerting, feeling his cock regrow and his hair receding back into his skull, but he was just glad it was over. 

“Okay, just a little hiccup.” He told himself. “Nobody needs to know. I bet loads of guys have had that happen once or twice. Yeah…”

A knock at the door startled him as he heard Devon’s voice on the other side. 

“Hey, Sam, are you awake? I am making breakfast!”

A shiver ran down Sam’s spine, and he felt a pulse inside him, threatening to change him back into a submissive female, ready to be cared for by his male. Sam swallowed and willed the change not to happen, but it took more mental energy than he’d care to admit.

“I’m awake, but don't worry about me! I’ll make my own!”

“Really? You’re a terrible cook. Plus, I am making kelp cakes. Your favourite!”

Sam pressed his lips into a thin line; they were tingling, threatening to plump.

“I’m fine!”

“Okay, suit yourself! If you want bland toast for breakfast, go right ahead.”

There was a pause before Devon added.

“Are you sure you’re not getting sick? Your voice sounds sort of weird.”

Sam felt his cheeks flush, and he forced his voice down an octave. 

“Just half asleep! Now let me wake up!”

He breathed a sigh of relief when he saw the shadow beneath the door move away. Staying male had never been a struggle before; now, he’d almost changed a second time before breakfast. Sam swallowed nervously; something told him this wouldn’t be an isolated incident.  

This story will be uploaded biweekly until its completion, but if you can't wait. I have also released this, along with the other Siren stories over on Kindle! Rest assured though, the full story will be available here in due time.