(Mermaid!AU - Title from a Little Mermaid Song. Original)

Hello, i still have writers block, but i have ideas coming out the wazoo.

If my writers block persist, i may develop this too because i'm a moron like that and my brain works in mysterious ways. You should know by now and for that i apologize.

For now, however, enjoy this out of nowhere oneshot.

Hope you'd enjoy!

"Hey birdbrain, catch,"

Marco hadn't even fully turned when a thankfully soft piece of cloth smacked him right on the face. Somewhere nearby, there's laughter, obviously from the culprit who had thrown it, and as soon as he plucked the towel away from his face, he found him doubled over in hilarity just a few feet away.

"Funny," he groused, but was thankful all the same, using the towel to wipe the sweat off from his face and neck. He didn't even realized how much he had sweated until the towel turned damp once he was done with it, before slinging it over his shoulder, "Done with dinner preparation? Usually, you'll still be up in the kitchen at this hour,"

The man didn't answer, only smiling enigmatically at him as he walked closer.

He raised a brow when their distance was close enough, standing toe to toe.

"Hey, what—"

Suddenly, the man moved closer, and gone right pass him.

Marco woke up with a gasp, and immediately shut his eyes close once more when his vision was assaulted by bright ray of sun.

Once the headache that came from the unexpected brightness passed, he let out a groan and pushed himself upward, his hand digging to rough earth while the other covered his face, wiping down lethargically. In the distance, he can hear the sound of rolling waves mingling together with the gentle caressing of plants, which jogged his memory about his current situation, as well as what led him to this particular place.

Images of his dream slowly came back to his no longer fuzzy mind, and in recollection, he took a deep breath, dropping his hand down with his eyes still closed.

Right.

It's been a month since he lost his brother, the very figure haunting him in his last dream, which means it's also been a month that he had been on the pursuit for the person who had caused it.

And it was all going smoothly, if progressing too slowly for his liking, but he had only recently receive a clue as to where his target had gone to and he had been on a chase since. He had been flying for 3 days straight without a break when he was hit by an unexpected storm, and the last thing he remembered before this very moment had been being swept away by the turbulent. So it would seem that he was carried to this place, thankfully still alive although admittedly aching just about everywhere.

Speaking of…

Where exactly is 'this'?

Blue orbs just a shade darker than the sky above blinked open, darting from corner to corner. It would seem that he's in a forest right now, in the middle of a clearing of sorts. There's fallen trees here and there, an evidence of the storm that had carried him, and if he looked beyond the thick wooden forest, he could almost perceive the wide expanse of sea just beyond, which explains where the sound of waves came from.

With another groan, he stood up, dusting his clothes and pants away from any dirt and grass. He must be way off from his original course right now, and the sad thing is, he didn't have any idea just how far away he was. The log pose should be able to tell him, but he'll need to find his belongings first, provided they hadn't been carried away somewhere else by the storm—

A low rumbling was heard from his stomach, a small sound made louder by the very palpable silence around him and Marco grimaced.

Maybe after some food.

Well, this is quite the predicament.

He didn't find his belongings, he didn't find any telltale sign of life, and more importantly, he couldn't find a single thing around that can be eaten. Worse yet, the one thing he did manage to find, his log pose, was shattered in pieces, with the needle bent beyond belief and with no chance of fixing it to at least tell him his next location. Which means even if he wanted to, Marco wouldn't know which direction to take to the nearest inhabited island.

His stomach growled again and he bit his lower lips, trudging heavily across the damp land.

By now, the sun has reached its peak position on the sky, which at least could tell him that its around mid day. He's wasting time as it is only walking around, should he take a chance and choose a random direction? Sooner or later, he'd come across someplace else, which is better than staying in one place and being continuously starving. There's not a single fruit growing on the thick foliage above his head, no fishes by the shores, absolutely nothing.

Sighing, the blonde man pushed back against thick series of bushes. He heard a stream coming from this direction earlier, maybe he can at least have something to drink first just to make sure he won't get dehydrated—

Actually, never mind. It seems like he already is and it's affecting his brain.

Because there is no other explanation as to why he's seeing not only a small waterfall which he was sure caused the sound of running water, but a large, multicoloured fin the colour of darker sunset jutting out of the jerky waves, flapping back and forth in an almost hypnotizing motion. With wide eyes, Marco approached, already feeling his mouth watering at the thought of how big the fish could possibly be and how it could immediately sate his hunger.

Once he was close enough, he braced himself, ready to transform his feet into talons in order to pierce through the regrettably beautiful scales soaked inside of the stream, when something else unexpected happened.

The fin stopped their swaying and made a sudden rush for him, hitting him by the stomach and knocking out his breath. Marco stumbled backward, surprised by the blow, but before he can even regain his balance back he was suddenly forced down by another, recognizably human body, strong hand clutching themselves around his neck and pressing against his windpipe harshly.

"Who are you?!" his assaulter shouted - there's someone else here, after all? How come he hadn't found a single sign of them beforehand? - tightening their grip around his neck, " How could a human reach these waters?"

In reply, he could only cough and sputtered as he tried to claw the hand away from choking him, only barely aware of the dripping all over his body and face, and how cold and clammy the other person's skin was against his own. With some effort, he opened his eyes, and for a second, stopped moving.

The person above him was undeniably male and naked, at least as far as he could see down his chest, with angry eyes the colour of last night's stormy sky and freckles dusted across his cheeks like the late night stars. Wet, dripping dark hair framed the youthful and aggressive sight, curled and plastered against fair skin, and even with the unsightly snarl that shows a series of oddly sharp teeth, Marco could only blink and found himself whispering, "…Beautiful,"

Dark eyes widened, as the man - boy? He looks quite young - loosened his grip around his neck and seemingly unconsciously moved back, looking as bewildered as Marco think he himself felt, "Huh?!"

But being freed from the choking grip barely registered to the dumbfounded man, as he glanced his eyes down and saw something utterly impossible.

The dark haired male was naked indeed, but instead of a pair of legs, what was attacked to his waist was an honest-to-all tail, a fish tail even, the very same tail and fin that he saw earlier from the water stream. Fragile, spiked and translucent fin fanned out on the ground in a display that reminded him of the softest silk one of his brother owned, a gradient of fiery red and cheerful yellow that dipped into the darkest black trails up to the shapely tail that hit him earlier, dispersing into little dots that decorated scales the colour of setting sun against lightly tanned skin.

"You're beautiful,"

The merman's face began to colour, freckles seemingly blooming as deep red flush settled on his cheeks and he jumped back, hissing, "You— How could you reach this place? No human was ever supposed to find this location,"

He should probably answer, but Marco found himself tongue-tied, unable to even register that he's being asked a question.

A merman. Unless he's severely hallucinating right now, he's actually seeing a merman.

(Well, that explains the 'human' comment)

Nevertheless, there hasn't been a sighting of one in over centuries. Merfolk were incredibly secretive, so much so that their existence as a whole was forgotten and often thought of as a legend. The fabled kingdom of Mermen, Raftel, was the dream of every single young boys and girls, and the journey to discover them was the end goal of every pirate out roaming the 4 seas, in hopes to not only uncover the legend of the merfolk but to also gain their treasure, the famed One Piece.

And Marco just found one of those legendary creatures.

All because he's so goddamn hungry.

"Hey!' webbed fingers were snapped in front of his eyes, making him jolt out of his reverie. The blonde looked up to see those previously confused and startled eyes turning angry once more, with the snarl back stronger and more menacing than ever, "I'm talking to you! How did you get here?! No human were ever supposed to found these waters,"

"I don't even know where i am," he answered truthfully, still completely baffled by this entire turn of event. A merman. Holy shit, he's seeing, talking and almost thought of eating a merman, "I was carried by the storm,"

The merman's eyes narrowed, cocking his head over to the direction of the sky. As he does this, his tail flopped a little and his long, flowing fins made a little wave motion. Marco's gaze was instantly brought back to it, eyes unable to look away in admiration, "Storm? That storm wasn't big enough to carry a human,"

"I wasn't exactly a 'human' when it blew me here,"

Again, the merman narrowed his eyes even further in suspicion, and even without saying, Marco can practically feel his demand for him to explain, "I'm a Devil Fruit user. A phoenix zoan,"

Instead of accepting that as an answer, the freckled male kept staring at him, the edge of his tail standing up and sending his fin into a wave. It looked almost like an unconscious gesture, much like how a human would unthinkingly move their limb while thinking, and for some reason, he found that incredibly adorable.

He chuckled, standing up, "I think it's best that i just show you,"

In a blink of eye and with a burst of blue and yellow flame, where he stood was now a giant bird with craning neck and fiery feathers, with strong, lean talons gripping down on the muddy ground. Marco looked down through hooded eyes, to see the merman's eyes turning wide as a saucer and his mouth gaping, completely astonished. Even the end of his tail stood up straight, quaking in either surprise or in preparation to strike.

"What are you?! How could a human turn into… into… " he trailed off, biting his lower lips with sharper row of teeth, "A… devil fruit, you say? Are you talking about the cursed fruit?"

Marco turned back into a human with ease, as he pondered the question. He knew that even between humans, the Devil Fruit were known by different names, and he supposed in a way, they are quite cursed indeed, "That's the one. I ate it a long time ago, and it gave me the power to turn into a Phoenix, the bird you saw earlier,"

"They gave you power?" the merman seems genuinely confused, "I was ever told they killed you instantly. Well, to merfolk, at least,"

Which, in a way, Marco thought made sense. In trade of his power after all, he lost the ability to swim, and he heard of Fishmen - another aquatic race that was much more well known and common - who did as well once they consumed a Devil Fruit. Unlike Fishmen, who can still withstand walking above water, Merfolks supposedly cannot live too long outside of the water, becoming vulnerable, so eating a Devil fruit would probably kill them instead.

Not that he knows; unlike Fishmen, who lived in - relative - harmony with human, no one has ever seen Merfolks in over centuries.

His stomach rumbled again, much louder this time, and Marco groaned, squatting down on the ground. Right, the big fish turns out to be a living merman, and no matter how hungry he was, there is no way he's going to eat something that looked like him, even only from the top half. At least the water seems safe enough to drink, but quenching his thirst is not quite enough.

"Hey, um, are you alright?"

Though half-lidded eyes, Marco looked up to see the merman again, who had slithered closer and now had a frown marring his face.

Sighing, he nodded, "Yeah, i'm.. i'm just hungry. I was on my way someplace else before the storm hits and brought me here, and before that, i hadn't eaten in 3 days,"

The merman let out a small, surprised noise, "That's…," Marco hear him trail off, and without any warning, he slithered back to the current, using his front arms to move and dipped back into the waters with only his fin again showing up. He reemerged a second later, one hand still submerged into the water as he used the other to wipe his hair back and made a leap over to the stream's ledge.

"Here," he said as he tossed over whatever it is that he had caught. Marco raised his hand up in reflex, finding himself holding something wet and slimy, which suddenly began squirming in his hold that he almost dropped it.

It's a fish, Marco discovered, the merman had thrown him a live and squirming fish.

"I saved him up for later, but you seems to need him more than i do,"

Marco looked at the merman, down to the fish and back to the merman, who was looking at him almost expectantly, "Oh, uh, thank you,"

The fish was on the smaller size, hardly bigger than both of his palm, but by just looking at it made his stomach churn, as if reminding him that food is food, regardless the size and state of rawness. Briefly, Marco thought that his brother would've disapproved of this line of thinking, perhaps insisted in taking it away from him and making him wait until he can come up with some recipe or another.

Marco smiled bitterly, as he opened his mouth and get ready to take the first mouthful bite out of the slimy and squirming fish.

"Hey!" a sudden splash halted and startled him, when the fish was suddenly taken away from his hand, "What are you doing?! You humans really are barbaric!"

In confusion, Marco could only blink, finding the bewildered merman looking at him with disbelieving eyes while gripping on to the fish, "Huh?"

"You were just going to eat him like that? You're not going to put him out of his misery first? That's so cruel! Even after he's okay with you eating him!"

Did he actually hit something while landing here or did his hunger affected his brain's function? Because he cannot understand a word that the merman was saying, "I… uh," he glanced from the still enraged merman to the fish, its (his?) gills puffing open and close repeatedly and the mouth twitching every so often, "I'm sorry?"

"You damn right, you should be. Fishes are okay with being eaten because that's their role in the ecosystem, so you have to show them respect for giving you sustenance in cost of their lives. Ugh, you—" the merman suddenly paused, turning to the fish in his hand with a concerned frown, "Oh, really?" he mumbled, and Marco must be going crazy, because it looked like he's talking to the damn thing, "Then why did he— Huh, well, if you're sure, i guess,"

When the merman looked at him again, he still held some semblance of doubt, but eventually he offered the fish back, "He said human usually do kill them first before eating, but you're probably just hungry. If you apologize to him and promise to kill him first, he said it's fine for you to eat,"

Marco blinked once, twice, several times.

He heard of 'respecting the nature', but this… certainly is a new level.

His stomach growled again though, urging him to go through with it, "Um, i'm sorry, uh… Mr. Fish?"

The fish's bulging eyes seems to focus on him, and its mouth twitches. Marco must be going insane, but it looked to him like his apology was accepted.

"Good," the merman took the fish away again, bringing it close to his face with a benevolent smile. He looked dazzling that way, without the snarls and the frowns, and Marco once again found himself staring, "Thank you,"

The merman raised the fish above his head, and slammed it down to a rock by the stream's edge with one powerful blow.

"The fuck?!" Marco jumped, because holy shit, he did not expected that. The fish was limp on the merman's hold now, and odd as it is, he actually felt sorry now for the little guy, "You just told me to respect him and all and now you just crushed his head?!"

As if he had done nothing wrong, the merman rolled his eyes, "Duh, it's the quickest and most painless way to end their lives, so they won't have to suffer. You humans really are clueless," he tossed the now dead fish back to Marco, but the man missed catching it, only having aquatic animal flop lifelessly on his lap, "There, his school almost always gets the best algae so you can know for sure that he's healthy and taste good,"

He actually did, raw and all, or maybe it was because Marco was so goddamn hungry.

The zoan user was still in the middle of licking his fingers and picking his teeth for some stray scales when he heard the merman laughed lightly, and found him half submerged back into the water, his top half leaning on the ground and looking at him in amusement, "You know, you're not bad for a human," he mused, smiling slightly, "I was always told that humans are evil, that they'll kill me on first sight and that they're always cruel to merfolks, but so far, you've been pretty nice, notwithstanding trying to eat a fish alive,"

Marco swallowed, feeling the slimy and cold fish meat sliding down his throat and filling him to some degree, "I've never met a merfolk before, so i don't know what to say, but you've fed me so i'll say the same about you,"

The merman suddenly turned glum, his lips downturned as he sighed, "I know. No one's allowed to ever leave the kingdom for hundreds of years now," he scoffed, "I'm not even allowed to leave the castle most of the time,"

Castle? "And by kingdom, you mean Raftel, right?"

The dark haired merman nodded. Then the very next second he suddenly turned alert, "Fuck, i'm not supposed to say that,"

Marco couldn't help it, he smiled, saying reassuringly, "It's not a hard thing to assume. Don't worry, i won't ask or anything,"

He was still stared at with some degree of distrust, but after a while, the sunset coloured merman seems to ease up again, "Right. Well, i guess that's fine. The only humans i'm supposed to be wary around are pirates. Whatever that was,"

Marco nearly bit his finger, and decided to do it anyway to stifle his choking. Shoot. Well, it is understandable why they'd be wary of pirates when the entire goal of being one is to find their kingdom and rob them of their most precious treasure.

The blonde cleared his throat instead, and in reflex pulled his shirt close to cover the very obvious tattoo on his chest. It was probably unnecessary, considering that since the merman doesn't seems to even know what a pirate is, there's very little chance he'll connect his tattoo to one of the biggest and strongest pirate crew in the seas, but Marco's can't help but to be self-conscious either way. He doesn't really want to make this merman distrust him.

"So why are you here then, if Merfolks are not allowed to leave their kingdom? I'm assuming it's nowhere nearby?"

The merman turned sheepish for a while, but the line of his lips turned tight, "I'm chasing after someone, a human pirate, at least that's what he called himself. He stole something really important to our kingdom, something that if it falls to the wrong hand, mean my people will be in danger," behind him, emerging from the water, his tail flicked, the movement stuttered and tense, and his face darkened in anger, "and in that process, he hurt one of my brother,"

The small bite of fish meat fell out between Marco's teeth as he gaped at the merman. That's… that's quite the coincidence.

"Me too," he rasped, biting down the bitterness that began to bloom in his chest, "I'm on a chase for someone. He… he killed one of my brother, and stole something dangerous. I have to stop him before he can cause any further destruction and as a payback,"

A plopping sound from the stream marked the merman's tail curling back down to the waters, the fin gently floating along the surface as he gazed at Marco with pitiful eyes, "I'm… i'm sorry to hear that. My brother was hurt, but he's still alive. I can't imagine what i'll feel like if i lose him,"

Marco could only smile, halfhearted as it is, "Thank you,"

On the overhead, the sky began to darken, splotches of red decorating the previously bright blue. It's getting late, Marco thought, and he should really be on his way.

Still, where exactly is he?

"I don't suppose you can tell me which direction to take, can you? I should leave soon, but it's too dangerous to go without any set direction,"

The merman perked up, "Oh, right, you can fly unlike other humans," he hummed, staring to the distance where the stream leads, most likely to the seas, "Well, it's a little tricky. No human were ever supposed to come close to this place, but since you said you've been brought by a storm, it kind of made sense. You probably couldn't have found this area on your own,"

Sounds like this place was much further away from where he had been originally. Shit, he's been wasting precious time then. Who knows if his target was still where he is.

"Okay, you look nice and trustworthy enough, and it is also my duty to chase away any unwanted guest," the merman spoke again, a hint of smile on his face, looking much more friendly than he had been just a while ago, "Well, usually that means killing and drowning you, but you're not a pirate and you only got here by accident, so it won't be fair if i did,"

Marco swallowed, "Y-yeah,"

At least his nervousness went undetected, because the merman only smiled, "I'll tell you what, i have to go on with my journey too anyway, so i'll lead you the way back to the human waters. It's not too far, and from there, you can go on your way again and get revenge on the man who killed your brother,"

There's a clench in his chest after hearing that sentence, but Marco nodded resolutely, "Right, and you need to find the one who hurt yours and stole your kingdom's treasure,"

"Exactly," the merman nodded with an equal amount of conviction, "Oh, by the way, my name's Ace. Humans also have names, right?"

Ace, what a nice and very fitting name.

"We do. I'm Marco,"

"Marco," Ace said slowly, as if testing his name and damn, it sounded nice to hear his name from that voice, "Alright then, Marco. What do you say we make our way out of here?"

Ace's tail design was inspired by Siamese Fighting Fish because one, they're beautiful, and two, i have one at home, and three, appropriate to their name, they fight everything and i don't think any other combination can suitably match best boy better.

Thanks for reading and hope you liked it! Please tell me what you think!