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Ochako Uraraka was an exceedingly skilled thief. Katsuki would give her that. The woman had a reputation. Very few people saw her, but her popularity preceded her. People knew that a robbery had been orchestrated by her when the next day the fishermen's nets caught treasure as well as fish.
That adorable face liked the recognition.
Katsuki was one of the few who knew her, who knew who Ochako really was. They had grown up together, in the same fishing town that had eventually become a junkyard and repair area for warships. Ochako came from a family of fishermen, and they had experienced firsthand the blow of the war and how their family had had to change professions to survive. Katsuki's family had been blacksmiths and at first, they had only had to specialize in their trade.
Until the soldiers thought it was fun to exploit them. The sieges and attacks had impoverished everyone. What had once been a small fishing town had ended with its polluted seas and sick people.
And one day, Ochako had disappeared.
Katsuki had chosen to retaliate against the kingdoms that had used his town as a playground. He, along with other young people his age, had made a series of decisions that had led to their own reputation. Eventually, they ended up on a ship and claimed the black flag as their own. Katsuki had found himself in the position of captain, more by force of will than by a conscious decision made by the crew and himself. And his pirate ship began to destroy those who deserved it. Katsuki and his crew sailed the seas answering to no one, exploring new cultures and cities without stopping.
So, he wasn’t surprised to meet Ochako again. It was as if part of him had known this would happen.
First in one port or another. Sometimes in a tavern. People didn’t know that the melodious voice of the beautiful singer was the thief Uravity. Quite an appropriate name for someone who had proven that there was no treasure big enough for her. At first, she and Katsuki recognized each other with glances. And he had been satisfied with those simple encounters. But eventually, it wasn’t enough. Later Katsuki sent spies to the ports to find out if a new singer had arrived at the place and only then anchored. Katsuki couldn't explain it. But hearing Ochako sing had always been something that centered him. Everything became clearer when he enjoyed her voice. And days later he could still hear her in his dreams, while he slept on his ship.
In this way, Katsuki connected that Ochako was Uravity. Where she was, a robbery would happen. And he was impressed. Ochako's guts were almost terrifying. She worked alone and it seemed almost like magic.
And when he entered the tavern, Ochako smiled at him. She was smiling at everyone, but there was some recognition in her gesture. They didn't speak. Ochako was using her singing career to inspect the area of her next robbery and he was at that port getting supplies. Katsuki wasn’t going to distract her from her work. So, he just watched her execute it. Ochako started in a tavern, eventually someone important heard her, and she became one of the guest artists at important events. And on any given night, Ochako would do one big hit or multiple little ones. And she disappeared.
The next morning the fishing nets caught treasures.
Admirable. Katsuki couldn’t classify Ochako in any other way: Admirable.
Things had been fine that way.
Ochako with her robberies. Katsuki with his attacks. They danced in the same line of work, but they didn’t coincide. He had been content to watch her work. The rest of his crew had also recognized Ochako. After all, they came from the same town. But they believed that she was a singer and nothing more. For some reason, he liked to keep Ochako's secret.
Katsuki knew that everyone believed that he was in love with Ochako because of the way he was looking for her. No one told him directly, but he knew.
And they were right. Katsuki wasn't hiding it.
But it wasn't like that meant he was going to do anything about it. Katsuki wasn't going to distract her from her work and Ochako definitely wasn't going to distract him from his. Katsuki respected her too much to intervene while she was working. He was satisfied with knowing her secret and hearing her sing.
Perhaps Katsuki was waiting for something.
And things would have stayed that way if it wasn't for Uraraka having the audacity to steal from him. The day after landing his loot, she had taken absolutely everything. It wasn't much, but it was one filled with valuable jewels that they had managed to get from a merchant's ship.
And even if it had been a loaf of bread…
The most relevant of all was Uraraka's audacity to steal from him.
The next day the fishing nets of his own crew had pulled the jewels out of the water. As if Uraraka hadn't wasted any time telling Katsuki about her little trick. And he found himself marching to the tavern where he knew she sang, not answering the questions of his crew, not telling them that he knew who had dared to rob them.
The audacity of that woman!
It wasn't hard to get the information he needed from the barkeep. Uraraka had a room there and a few hours ago she had returned. Katsuki marched up the stairs, not knowing exactly what he would do with her when he got his hands on her. But he needed to teach her a lesson. Katsuki needed to know why Uraraka was seeking to upset him.
The tavern, like all the ones Uraraka used, had a view of the sea.
That must have been his signal that something might happen.
But Katsuki had been impulsive in breaking down the door. And for a second, he had completely forgotten everything when he saw Ochako, sitting on the windowsill, looking at him as if she had been waiting for him.
As if he was late.
Ochako wore a redshirt as her only garment. It was too big for her and fell over her shoulder, revealing her skin. She smiled at him, as she always did when she looked at him.
Katsuki took a step into the room.
She brought the shirt sleeve close to her nose and took a deep breath. Her eyes closed longingly and then she gave him an analytical look.
A look that was a direct hit.
“Is that my shirt?”
The shirt he had worn the day before, while they were unloading the loot. The shirt he had taken off in his cabin and Katsuki hadn't noticed was missing.
Ochaco smiled.
How had she gotten onto his ship?
Katsuki took another step forward and she fell back.
There was no time for anything. Instead, he ran to the window and looked down. To the sea. But Ochako didn’t surface. He stood there looking out at the calm waters and she didn't surface.
“Dammit…”
Katsuki was about to jump out the window when he heard Ochako's voice echo across the harbor. Katsuki frowned, but little by little his body relaxed. He shook his head, trying to focus on the anger he must be feeling, but it was as if his mind had other plans. His shoulders relaxed and his breathing became slow.
It couldn't be…
That was the first time he heard Uraraka outside of a tavern environment. Katsuki had assumed her voice calmed him because it was about her. Because he wanted to relax listening to her. But that moment was different.
Uraraka's voice was supernatural, a song that called him to look for her.
Katsuki couldn't get his mind off the way she had closed her eyes at the smell of his scent on his shirt.
He must be upset!
Instead, he could only think of her wearing his shirt.
His body tumbled out of the room and back onto the main street. Uraraka's voice was still present, and it seemed that he was the only one who heard her.
A mysterious, wordless voice. Her singing was something that resonated with his core and pulled him through the streets like a lost man.
In other circumstances, Katsuki would have been upset. No, he should be upset. That was what was consistent with who he was and the moment he was living. Being caught like that would be reason enough to get angry.
And it was.
But Katsuki felt none of that. And it wasn't just the effect of that eerie voice wrapping his body. But that his mind had found that maybe that had been holding him back for so long. The real reason why he had stood aside, aware of his feelings toward her but doing nothing about them. Because he didn't know how Ochako felt about him.
Until that moment.
Katsuki smiled mischievously.
Ochako had used her prodigious abilities to get his attention. She had executed her plan, like so many other times, but for Katsuki to look for her. And now, Ochako was guaranteed, one way or another, that he would come looking for her. If it wasn't an obvious declaration of intent, Katsuki didn't know how to interpret it.
Even more so when Ochako's audacity made him go outside the city, through the most dangerous paths, to end up where everything had started. In the cave where he had hidden his loot and she had stolen it.
The second Katsuki entered. The mysterious voice fell silent.
A river crossed that cave, connecting with the sea. There was only one entrance, and it was hidden by vegetation. Even so, the cave led to multiple paths and dangerous routes. Most of the time it ended in precipices in the dark or dead-end waterholes. But Katsuki knew the area. And apparently Ochako too.
Still, he smiled and walked to one of the wrong routes.
Ochako's voice came back for a second, pulling him in. But she kept quiet because she must have realized what Katsuki was doing.
He laughed wickedly.
The audacity of this woman.
The river water whipped as if a creature had hit the surface in frustration.
“Are you going to tell me what you are, Cheeks?” Katsuki walked along the riverbank. “A witch? A ninja? A spirit?”
The water waved a few meters ahead of him.
Katsuki smirked. Ochako could be proud and very skilled. But it was easy to provoke his precious ego.
“Aren't you going to talk?” He stopped and listened intently.
The light was dim in this part of the cave. Usually, by now, his crew would be lighting torches. But he didn't carry any. Ochako brought out the worst in him. The best of him. Whatever it was, it was something that came from deep within him. Still no answer. Katsuki raised his eyebrows. Could she look at him in that darkness?
“If it's going to be like this...” So he didn't tempt the possibilities and kept his face indifferent as he turned back the way he had taken.
Something came out of the river. Katsuki had no time to analyze it. Because whatever it was closed on his ankle and pulled him into the water.
On instinct, Katsuki tried to fight. But under the water, the enigmatic voice returned. His body relaxed into the darkness of the water and gentle hands cupped his face as he was dragged away from the surface. Ochako. She was there, guiding him with eerie elegance far below the surface. Suspending his body in the water. Taking away his control of absolutely everything.
Only her voice surrounded him.
The cold water and her voice.
And it was just like the other times in the tavern. Just hearing her, Katsuki fell under her spell. Because it had to be that. Which should and usually would annoy him. But the anger didn't come, and it was something bigger than whatever she was doing to him. Ochako's voice seemed to speak to him, and it was his body that decided to listen. It didn’t make sense. None of that had it. But Katsuki knew that something in him was making an active decision to follow her. Or in this case, to block his survival instincts so she would take him with her.
Katsuki trusted her.
Ochako rewarded him with her lips pressing against his. And Katsuki took her by the waist, discovering her naked torso, and pressed her against his chest. Feeling her. Enjoying that moment that could be death's door for him, in complete darkness and finding it satisfying. She dared to laugh against his lips and even though there was no light, Katsuki could feel her smile against his lips.
‘The audacity, my captain.’
Katsuki would have to admit it. It wasn’t his brightest moment. But he tried to answer her. And the moment he opened his mouth, the water entered and burned him. Ochako began to swing faster. He could feel the movement of the water as if he was carried at great speed. The human mind was curious when it came to things like that. Even though his survival instincts told him to fight for control, his body seemed to know that everything would be okay. Little by little they approached the light and Katsuki looked at her. At least what he could see of her as he was pressed against her side.
Ochako looked determined. Despite having a sweet and kind face that made everyone call her an angel, Ochako could look like this. Intimidating and dangerous in her determination. Katsuki found himself smiling. And that was the second they surfaced, and she hurled him with superhuman strength toward the shore. Katsuki growled, feeling like a wet dog, rolling around on the ground and hearing his mistress laugh at him. Damn, Katsuki was a pirate, not something she could use for entertainment. It didn't help his case that he finally regained his balance, ending up on his hands and knees. Katsuki felt anger boil his blood and raised his head, ready to remind Uraraka who she was dealing with.
“You could have more—!”
His voice choked as he watched her swim on the surface of the water.
A mermaid.
Ochako was a mermaid.
Her hair floated like a crown around her face. Her skin had a pearly shine. Pink. She was pink. Her skin looked as usual, creamy and smooth but now there was a slight pearly touch to it. Her torso was also uncovered. And he had to remind himself how to breathe at the sight of her like this. Many female pirates wore only a shirt and on most occasions, their breasts were in plain view. Sometimes out of pride, to show their enemies that they died in the hands of a woman. Others because the sea was fairer. Katsuki couldn't expect the women of his crew to cover themselves more in the scorching heat than the men. Also, after the first impression, it was easy to remember that breasts were a taboo in society. Not by nature.
And even so. Despite remembering all that. Katsuki had to force himself to think that there were more important things than that celestial image being illuminated by the natural opening of the cave. And with a smile, he kept looking down. To the soft belly, wherefrom the height of the navel a gentle transformation took place. The skin changed to a coral color and took on a texture similar to that of a dolphin's skin. Ochako had no scales. But she definitely had a tail. And when she turned around, he could see a small dorsal fin resting on her ass. Katsuki found himself smiling once more. The soft coral color was quickly transforming into the deep pink that he had always associated with her.
She was beautiful. The kind of vision that legends gave. An excellent reason to jump into the sea.
Ochako stopped showing off for him and sank back down until her body was hidden up to her waist.
“Is this how you escape with your loot without needing a ship?”
She smiled. Her little pearly teeth were now slightly sharp. A predator. Katsuki shivered with pleasure.
He always knew that Ochako was dangerous, but this confirmed things more.
“Really? Is that your first question, Bakugou?”
Her voice continued to overwhelm his soul, tightening its grip until it caught him.
Katsuki looked around. They were in the place where his loot should be. But the cavern was empty. Instead, all he found was his redshirt. The one Ochako had been using in her human form and now rested with almost loving care on the rocks, just where the sun could dry it.
“I don't know...” Katsuki shrugged. “You seem very excited about telling me things. And I’m tempted not to give you that satisfaction.”
Ochako took the bait. She swam towards Katsuki. Her body sank into the water, dipping and resurfacing like the dolphins when they swam alongside his ship. But Ochako wasn't playing. She reached the shore and put her hands on the rock to support her body so that she was face to face with him. Despite how different she looked, Ochako kept puffing out her cheeks when upset.
“You are mean.”
“I’m a pirate.” He dropped his head on his shoulder. “And you are a thief. A very good one.”
Ochako smiled again at the recognition. Oh, she liked flattery. He could work with it. Surely, like Uravity, she couldn't take many of those.
“And very clever too. You took my loot.”
“And your shirt,” Ochaco smiled. “But technically I've returned everything.”
Katsuki raised an eyebrow. She leaned further in his direction. Despite being wet and full of dirt, he could feel the mermaid's body pressing against his as if nothing separated them. Ochako raised her chin to meet his eyes.
“The loot wasn’t my real purpose. Just like your shirt. Your treasure is under your ship. Your shirt is there.” Ochako barely moved her chin. “And your mermaid is here, Bakugou.”
As when the ship fell prey to rough seas, her words felt like falling from the crest of a wave. Ochako still had the scent of the sea and the sparkle of mischief in her eyes.
“So, you did all this to get my attention?” He smirked.
That was the biggest compliment Katsuki had ever received. Greater than being considered the most dangerous pirate.
But Ochako laughed with delight and shrugged. Entertained with his question, as if Katsuki were a child avoiding the correct answer.
“What can I say? I got tired of waiting. You didn't do anything. Despite…” She waved one hand. “Everything.”
Katsuki noticed the sharp claws that Ochako had.
“Everything?”
Ochako pressed her index finger on Katsuki's chest.
“I am your singer. Your soul responds to my voice.” She frowned as if that was universal knowledge. “Usually, when a human hears their singer's voice, they jump into the mermaid's arms. They don’t look at her for days without moving a muscle. But I know that I’m your singer. You are just too stubborn!”
“You're talking out of context, you know that, right?”
Ochako's cheeks turned pink and puffed out, like peaches. Katsuki leaned toward the predator in front of him. Ochako exposed her cheek to him as if she knew his most ridiculous desires. Katsuki found himself smiling as he bit her gently. Because he wanted. Because he could. Because it seemed like the right thing to do when his siren called him out for having willpower.
“Mermaids breed with humans. My father explained to me that it’s the way we can be on land and at sea. A way of survival.” Ochako frowned when he stopped biting her. “Mermaids mate for life. And because humans don't… There's this special bond. The song of a siren attracts her destined mate, and they’re loyal to her because…”
Ochako didn't continue, perhaps because it meant to talk about the effect she had on him. But Katsuki knew that part well, he had been suffering from the symptoms ever since he first heard her sing.
“Your voice has me trapped. There is no one else for me.”
That must have sounded terrifying. No, that must sound like his decisions were taken away from him. But the truth was that Katsuki had been in love with Ochako long before she cast a spell on him. If she wanted to call him a destined mate. It didn’t matter.
“But you were doing nothing, Bakugou,” Ochako claimed. “I was there... and you were doing nothing!”
“You were on a mission. I wasn't going to interrupt you or distract you from your work.” Katsuki felt offended that she believed that he would put his romantic fantasies above the work that Ochako did.
She seemed to understand because she laughed. Ochako looked at him as if it was new for her to be someone else's priority. Which was absurd. She deserved respect. Admiration for her work. And be treated professionally.
And as her only warning, she glared at him just before she tossed him into the water.
His siren was bold.
Ochako sent him flying over her head. Like a dolphin playing. Katsuki fell into the water, but he did so more gracefully. And she quickly caught him and brought him to the surface.
“I'm not—”
But she kissed him. Ochako leaned over his body, sinking him into the water and taking his face as if he was a delicate piece. And she kissed him with a smile. So, he decided to excuse her for being so impulsive. At least for that time. Katsuki took her by the waist, caressing her skin. Ochako had to pull them to the surface and began swimming on her back to keep them afloat. Katsuki was fascinated by how strong she was. Ochako carried him as if he weighed nothing. And Katsuki had to admit it. If Ochako had seemed like a dream come true before, the discovery of this whole new set of predatory abilities had made her perfect.
“Sirens accumulate things that we like.” Ochako nuzzled her nose against his cheek. Apparently, she liked close contact. “And I'm tired of not having you, Bakugou. I went into your ship because I got tired of waiting. And I thought it would be more fun to tease you.”
Katsuki searched her eyes and glared at her. It was like dealing with a mischievous and lacking moral creature as long as the goal was her satisfaction. Ochako was a good person, but she didn't seem to mind torturing him a bit and making fun of him. Katsuki could feel that his future was going to be complicated and on edge if he stayed close to Ochako.
By all things holy, he loved her.
“Say something,” Ochako frowned.
“Katsuki, who talks about mates and all that but doesn't use the correct names?” He gently bit her cheek and cupped her waist, feeling like he could float with her forever. “And we're going to need to organize—”
Ochako kissed him enthusiastically again. As a predator, it seemed normal for her to charge her prey. And he found himself again submerged in the water. Pulling away from the surface as soft lips swept over his and sharp teeth played with him. Ochako pulled away from him abruptly and he opened his eyes, meeting the predatory gaze of a beautiful creature. She was going to devour him, and Katsuki found himself satisfied with his fate. But Ochako shook her head and brought him back to the surface too quickly.
“I could have endured longer,” Katsuki argued the second he caught his breath. “You must not be so careful with me. You know I'm not made of glass.”
“What do you mean by that?” Ochako pushed him to the shore and pulled him out easily.
“Depends on what you need.” He tried to sound nonchalant because he didn't want to push her.
Katsuki definitely admired what Ochako was doing. So he couldn't tell her to take her things and live on his ship. As much as that was what he wanted.
Instead, he watched her swim near the shirt that was still wet. Ochako braced her hands on the edge and catapulted herself out of the water. Katsuki again forgot how to close his mouth and how to breathe. Mid-jump, Ochako transformed from mermaid to human and slipped into her red shirt. All in a matter of seconds.
A personal hideaway on a desert island.
That they needed. So that Ochako could be naked all the time. So, she could be in her two elements at will and he could admire her without stupid things like his shirt obstructing his view.
“Katsuki?” Ochako gave him an amused look.
“Don’t blame me.” He rolled his eyes and closed the distance between them. “It's not every day you see a sea goddess take on a human form.”
Ochako laughed out loud and when he sat down next to her, she leaned against his shoulder and bit him there. Her teeth were no longer sharp, and it had been a light touch. But it had felt good.
“You like to bite, don't you?”
“It's a show of affection between the mermaids,” Ochako replied.
And she would have said something else, but Katsuki grabbed her by the waist and sat her on his lap so he could reach her cheek and bite her again. She laughed, wriggling playfully on his lap.
“Are you telling me that I can bite these cheeks all I want?” Katsuki smiled darkly and made her jump on his lap “And can I bite other parts?”
“Katsuki!” Ochako took hold of his shoulders and looked at him with concern “Doesn't it…scare you? I’m not human. You saw how I look. Doesn't it bother you? On multiple occasions, I almost drowned you because of my impulsiveness.”
“I’m a pirate. Die by drowning is an expected ending.” Katsuki shrugged. “And what should scare me, Cheeks? You are fast, strong, and deadly. You're perfect.”
Ochako looked at him in surprise and hugged him, hiding her face against his chest.
“Mine.” She bit into his shirt, over his heart.
“That means…?” Katsuki ventured, sliding his hands down to cup her hips.
“I want to live on your ship. I will continue doing my jobs and I could help you ith yours.” Ochako raised her face determinedly. “Your cabin will be ours.”
Something told him that Ochako had already been thinking about all this in advance.
“Demanding,” Katsuki told her as a compliment, and she wrinkled her nose childishly.
“And much of your stuff will be mine. Mainly your clothes, they smell like you. And I like them.”
“We'll have to put—”
Ochako shifted to sit with her legs to the sides of his hips and rise above him. She took his face. Katsuki could see the predator that was actually Ochako resurface in her eyes.
“Mine.” Ochako reminded him slowly, running her tongue over her teeth.
Katsuki smiled. He didn't think boundaries worked with someone who dedicated her life to taking what she wanted. But surprisingly that didn't bother him.
“Yours.”
His siren was going to devour him.