Unknowingly Accepted

Unknowingly Accepted

Merman!Bakugo x F!Reader

NSFW

CW: (eventual smut), language, misunderstood mating rituals, possessiveness, jealousy, (mild) stalking.

No beta, we die like Endeavor's career.

Words: 4k

+PART ONE+ (1/?)

To say you almost had a heart attack was an understatement.

You had been sitting on the dock at your stepfather's beachfront house, your legs dangling over the side and kicking at the water with your feet. What you hadn’t expected was the blonde hair that broke the surface, making you shriek in alarm before your heart calmed slightly...momentarily. At first, you’d wondered what the hell a...handsome young man was doing in the water near your stepfather's house. It was pretty secluded. To your knowledge, there wasn’t another home for a few miles. Did he swim from a nearby home? These questions initially entered your mind as his crimson eyes stared quietly into yours, your mind not processing how strange this was...at first.

Your lips parted to speak, his crimson eyes flashing in interest as his muscular shoulders broke the water the same time his...tail did. All the words died in your throat as you stared in disbelief, blinking rapidly as the brilliant orange and black tail lightly splashed out of the water behind him. It was gorgeous, iridescent and massive.

You couldn’t move – you were in too much shock at what the fuck you were looking at. His handsome head tilted down slightly, his crimson eyes bright and questioning. His sharp, yet handsome face looking just as intrigued by you as you were him – though, he admittedly didn’t look frightened of you. You weren’t sure what expression was on your face, but you highly doubted it looked much different than a deer caught in headlights. His crimson eyes moved down your body, his gaze lingering on your bare legs and feet that were under the water. He was a few feet from you, and when he slowly moved forward, the humongous black and orange tail moving behind him...you regained control of your body.

He was so big. He could pull you under, he could – you gasped and scrambled backwards out of the water, your eyes huge as he paused in his approach. His brows furrowed slightly, as though your behavior perplexed him. He was looking at you as though he’d never seen a person before...but there was zero fear. Then again, why would he be afraid of you? You weren’t exactly threatening.

You’d heard tales of mermen...they were beautiful and deadly. But that’s all it was, wasn’t it? Tales? They couldn’t possibly be true.

You sharply stood, eyes on him as he moved a little taller out of the water in response, revealing a muscular chest. Your breathing was labored as you began backing up, swallowing thickly. He tilted his head a little more, his ash blonde hair cutting across his intense, ruby eyes that never left you.

No words were exchanged as you turned, grabbing the end of your dress and fleeing towards your stepfathers home. When you reached the porch, you paused, gripping the banister and breathing heavily. Part of you wondered if you had hallucinated as you turned, looking in the distance at the dock, only to see the gentle blue waves...no sight of a handsome, blonde man.

((O))

A few days had passed, and you couldn’t get the encounter out of your head. You told no one; you didn’t want them to think you were crazy.

Hell, if you thought too much about it, you thought you were crazy, too.

You had avoided going near the water again by yourself, your eyes constantly searching the water when you were near it. You didn’t see anything again, but in your paranoia...you felt like you were being watched – always. The second you stepped foot outside, that itching feeling of someone’s stare was all over you, making you uncomfortable.

You were warily looking over the water and walking on the dock with your stepfather when you felt a disgusting squish underneath your bare foot. You jumped back, shrieking when you saw a huge, dead fish on the dock. You covered your mouth with a gasp when you saw massive claw marks across its blue scales, obviously killing it.

“Shit, how did that get up on the dock – what the hell killed it?” you stepfather said after running up to you when you shrieked. You covered your cheeks, your stomach rolling in disgust when your stepfather leaned down to pick it up, it’s guts falling on the wood before he tossed it in the water.

“It’s alright, something else will eat it,” your stepfather chuckled, patting you on the back.

You swallowed thickly, wrapping your arms around your torso as he began setting up his fishing pole.

“I…what do you think killed it?” You asked in a high pitched tone, seeing him shrug uninterestedly.

“Could be anything,” he commented, inspecting his line, “ocean is so big that anything could be out there.”

You nodded, looking out over the water with a wary look.

Over the next few weeks, it kept happening. You always seemed to be the one that found the ripped apart, dead fish near the water. Multiple ones kept turning up, and to your horror, they kept getting bigger. You never wanted to go outside again when a medium-sized shark had turned up in your path.

What was worse was that every time you showed your stepfather, he’d shrug it off as though this was normal. You weren’t a marine expert, but you were pretty sure this was weird. You hated it, but your mind kept trailing back to the…merman you thought you saw.

Was he doing this? If he was and he was trying to unnerve you, it was working.Was he trying to frighten you? Why else would he be leaving carcasses everywhere? Of course, you didn’t know it was him, but you began to strongly suspect it.

You were sitting on the sand, rolling a rock in your hand and looking out over the water once again as your stepfather waxed his boat nearby. You sighed at the feeling of being watched, pulling you knees up to your chest and resting your chin on your knee. The sun shined down on the water as you contemplated why you were always out here, looking over the water every time you stepfather came out. Did you want to see him again to prove to yourself it was real?

You sighed, your eyes catching something gleaming at the edge of the shoreline. You paused, lifting your chin from your knees as you slowly stood, walking to the waters edge and crouching down. Sure enough, there was glimmering lights just under the surface, making you hesitate before reaching in the water and grabbing the object. Your heart stuttered when you realized there was a string, and you pulled it from the sand.

Your eyes almost popped out of their sockets when your hand revealed a stunning necklace. It was held together by an intricately braided string, unlike you’d ever seen before. What stunned you was how it was made. There were sea shells and what appeared to be diamonds and serpentine woven throughout the braided chain. You weren’t sure, but they certainly looked like them and you knew both were found in the ocean. The diamonds were cloudy as they were raw, but so gorgeous that they took your breath away. They fit the white of the seashells, and the serpentine added a pop of color.

It was the most unique necklace you’d ever seen. There was a simple tie in the back as you hesitated, then placed it around your neck. You smiled as you fastened it, looking down and running your fingers over the small gems and shells. You heard a small splash and looked up sharply, gasping when you saw a familiar, blonde head near the dock, about twenty feet from you. You stood on the shore, his intense eyes trailing down to your neck, where the necklace rested against your collarbone. For the first time, his neutral expression faded, his smooth cheeks crinkling as he smirked in what appeared to be satisfaction. It made him look more handsome than anyone had a right to.

At that moment, you knew he’d made it and somehow, made it for you. Your fear lessened, but didn’t become totally absent. After all, he was still some kind of sea creature. You glanced over at your oblivious stepfather nearby, noticing his gaze followed yours. His gaze moved back to you when you looked back at him and he tilted his head down as if to say, ‘What are you going to do? Cry for help?’

It absurdly kept your mouth shut as your heart raced in your chest. The sounds of the water and the gulls may have drowned out your words that left your mouth without a thought.

“Thank you.”

To your surprise, you saw his head and shoulders raise in recognition, his massive tail lightly moving the water behind him. It had to be uncomfortable, you thought, to be in the shallow water with a tail like that. It’s clear he’d only came to see you, making your chest squeeze. Every part of you said he was a predator, and you should be wary and worried, but….was he just curious about people? Was the necklace an offering of peace or friendship?

“Honey, could you come help me with this?”

Your stepfathers voice caused you to jump and look over at him as he waved you over. You quickly looked back, frowning when you saw he was gone. Clearly, he didn’t want your stepfather to see him.

You sighed, lightly touching the necklace as you went to help your stepfather.

((O))

“You love swimming, come on!”

It was how you ended up on your stepfathers boat with your mother in the ocean. You supposed that now, you were wary of the water. Not really because of him, but at the same time, it was because of him. Surely, there were others like himself? Mermen?

You wondered what his name was. Did he even have a name? Surely, he did. He didn’t speak and maybe he couldn’t, but his gaze was as intelligent and it was intense. His face was fierce, but incredibly handsome in your opinion. His skin was perfect, and not to mention, his upper body was completely ripped.  

Dear god, were you attracted to a fucking mute fish? 

You needed to get out more.

You were wearing the necklace you suspected he made with your bikini. Absurdly, you told yourself if any other…fish-men saw it, they’d somehow know one of them made it and leave you alone. You hesitated at the side of the boat, looking around the rippling, blue water as though you were going to see a face. It had an eerily resemblance to being too afraid to look out the window at night because you were afraid of seeing a face.

No, you doubted he was here. He went close to the shore when he wanted to see you. You weren’t far out, as the cliffs were nearby. Closing your eyes, you jumped in the water, the coolness rushing over you as you broke the surface, rubbing your eyes and blinking as you watched you legs move, a tad paranoid something was going to touch them.

Your stepfather and mother were drunk, laughing loudly on the boat as they blared classic rock. You rolled your eyes, swimming a bit away from the boat to avoid them. Honestly, you weren’t even sure why they insisted you go. You felt like you were intruding on a date or something. You swam a little further away, sighing to yourself and trying to relax, letting the water lap over your shoulders.

Pain shot fiercely up your leg, making your eyes shoot open before you shrieked and went under the water. Your leg locked up, and it took you but a moment to realize you had a muscle cramp.

Your mind was frantic as you scrambled for the surface, your lungs burning as you prayed your drunk parents would notice. Your vision started blackening when you felt something warm and strong wrap around you and break the surface. You coughed horribly as you felt yourself moving through the water at a fast speed, unable to focus or get your bearings and you choked and gasped. It suddenly stopped and you felt yourself being laid on a hard surface. Your coughing quieted down as your watery eyes tried to focus, making you rub them and blink heavily.

Your spine went rigid when you met a familiar, crimson gaze that was much closer than ever before. His upper body was pulled from the water, his tail still submerged as he leaned on his hands, looking over your body as if to check that you were okay. Your gaze flicked around, realizing he’d taken you to the nearest surface, which was inside one of the caves. Your gaze moved back to him as your heart thundered in your chest. His arms were corded and strong, looking like they should be considered weapons. He had firm pecks and and abs, making your mouth go dry when you saw the black and orange scales begin at his tapered waist, below his belly button. His hands were plastered on the surface next to you, your heart jolting when you saw deadly looking claws. Claws that likely made those fatal gashes in the sea animals left around your stepfathers property…

Your gaze moved up to his face once more, startling you when you saw he was already watching you look him over. It was completely against your will when you felt your face redden, taking notice of his eyes flashing as he clearly saw the change in your skin tone.

He tilted his head, his eyes roving down your body making you blush even more furiously, wrapping your arms around your stomach in embarrassment. Your bikini wasn’t really skimpy, but it still wasn’t a lot of fabric. He suddenly pointed a large, clawed hand at your calf, which was still twitching from the spasm.

“Pain?“

A jolt of surprised went through you as your mouth parted in shock at his deep, gravely voice. He could speak? It was clear that the word was somewhat unsure, and that your language wasn’t his own. But…how did he know? You’d had the feeling he’d understood your thanks, but now, it really seemed as though he had.

“…”

His brows furrowed at your response, or lack of response. His soft-looking lips pressed into a hard line, reaching forward and grabbing your calf, causing you to yelp in alarm. Fear traveled up your spine as you squealed and began to struggle, trying to pull away from his iron grip. He wasn’t hurting you, but the strength you felt in that grip scared you. His claws squeezing into the flesh of your calf.

“No…hurt,” he said in a deep voice, making you go still as you stared at him with wide eyes. His crimson eyes moved back down to your calf, a shiver running across your skin as his cool hands squeezed your muscle, moving up and down your calf with furrowed brows. You couldn’t move, but you felt like he was checking to see if you were injured…what you didn’t expect was the warm tingle that traveled up your leg from his touch, settling in your stomach. You bit your lip, feeling a tad disturbed at your body’s reaction. He was so handsome and strong looking, though.

Jesus, you were trying to justify being a little turned on my a fish?

“Hurt,” he said again, releasing your calf and shaking his blonde head. Clearly, he had deemed you healthy. Part of you wondered if he had just started learning you language a few weeks ago. If so, his understanding was amazing. Just from his gaze alone, you could tell he was very intelligent. However, if he managed to understand and even speak a little bit of your language in that short amount of time…that showed such a high intellect that you couldn’t help but to be impressed. Perhaps mer people were more advanced than humans?

“It was…a muscle cramp,” you said in a low, strained voice, his head tilting and his eyes lighting up at the sound of your voice – as though it made him happy. His face didn’t change, but his ruby eyes were very expressive.

He nodded as though he understood, his eyes moving back down to your legs and cocking his head, looking at your feet curiously. You didn’t move as his hand reached out again, slowly, as though not to alarm you. He ran a clawed finger across your toes, pulling back slightly in alarm when you wiggled your toes in reaction. It was clear that he’d never seen a human this close up before and had clearly never touched one.

Your fear lessened to almost nothing. He was frightening in many ways, but he was also…

Ethereal and beautiful. He had saved you and checked to see if you were injured. If he wanted to harm you, surely, he would have by now? Though he seemed intense and a powerful force to be reckoned with…he didn’t seem like he meant you any harm. Perhaps you were naive for it, but you felt yourself relax.

He was watching you intently again, the only sound in the dark cavern was the trickling of water and your slightly labored breathing.

“What’s your name?” you whispered, watching his eyes go down to the necklace around your throat. His ruby eyes flashing in satisfaction as he looked back up at your eyes. “Do you understand me?” you asked, shifting against the hard rock of the cave and pulling your legs underneath you.

He tilted his head, his eyes searching as he put a clawed hand to his strong chest. “Katsuki,” he said clearly, making your brows raise in surprise that he understood you.

“Katsuki...” you trailed off, jumping slightly when his eyes immediately darkened, a small growl rumbling in his chest and alarming you. You flinched back, causing him to immediately stop and lean a little closer to you.

You looked at him a bit wearily for moments as he waited for you to speak.

You swallowed, putting your hand to your chest. “Y/N,” you said in a soft tone, his upper body angling towards you a little more, his tail making a small wave behind him....as though you telling him your name really pleased him.

He paused, his eyes searching your face before turning and diving into the water quickly. You yelped in alarm, scrambling to the edge to look down into the dark water a bit frantically. Why did he just leave?

You looked around the cave, your shoulders hunching as you became aware of how dark and...creepy it was in here. You could swim back to the boat – did they seriously not notice you were gone?

My god. What if your leg cramped up again? Great, now you were traumatized.

Right as you really started to panic, he broke the surface of the water, shaking his hair out. To your amusement, it went right back to his spiky look as though it wasn’t just soaked. You couldn’t help it when a giggle left your lips, his crimson eyes snapping to you, his nostrils flaring slightly as he pulled his hand from the water, flinging a large, green fish on the rock in front of you. You jumped, gasping as you saw the familiar claw marks on the side of the dead fish, your eyes going wide.

“It was you!” You gasped as his brows raised for a moment, a smile curling his lips. Your heart jumped when you noticed his perfect teeth also had fangs – two sharp canines. “Why did you leave me dead fish?” You asked, tilting your head.

His eyes squinted for a moment, as though he was trying to process how to answer your question. “Hmm…showing interest,” he answered, his eyes gleaming as your face reddened.

Surely, he didn’t mean…

“What do you mean?” You squeaked, staring at him in disbelief as his lips curled in what appeared to be frustration, huffing through his nose.

“Interest…in mating,” he emphasized, your jaw going slack in shock as his eyes moved down to the necklace. “Accepted.” He added, nodding towards the necklace that adorned your throat.

You were reeling in shock. You’d accepted his advances by wearing the necklace he’d made? How was that fair? Surely, he knew that you didn’t know what it would mean.

He huffed, picking up the fish and holding it out to you. You recoiled, your stomach turning at the bleeding body. “Eat. Hungry,” he said, looking determined to make you eat this raw fish. You shook your head imploringly, covering your mouth and attempting to wave it away.

“Y/N!”

You jumped at the sound of your stepfathers voice. Katsuki snarled loudly at the sudden noise, turning around sharply and blocking your view with his large body protectively at the perceived threat to you.

“It’s okay!” You exclaimed, “It's my stepfather.”

His strong shoulders relaxed slightly as he turned to look towards you again. It must be your imagination, but you could have swore a sad look crossed his intense face for a moment. It was almost as if he was sad your time together was over.

“I have to…” you trailed off, sliding your legs in the water next to him as he nodded in understanding. You tensed up when he immediately moved in front of you, his large, strong hands wrapping around your waist. Your breath left you in a rush when he strongly lifted you off the rock, slowly lowering you in the water and supporting all your weight.

“Oh…” you breathed as he towered over you, coming much closer. He was huge as you stared up at him with wide eyes. “I-I…” words failed you as his hands tightened on your waist, his gaze becoming hooded. Your breath was shallow as a soft scent entered your nose. It smelt like the ocean, but it was almost sweet, like caramel.  It was crippling, and you found yourself unable to move or even think as his eyes fluttered closed, tilting his head down. You didn’t even think of stopping him as your own eyes fluttered shut.

The feel of soft press of his lips was unexpected, as was the feel of adrenaline that suddenly started pumping through your veins. Excitement rushed through you as you curled a hand in his damp, blonde hair that was surprisingly soft. He growled in your mouth, and you felt a hand on your waist curl to your lower back, pulling you flush against his hard body.

You weren’t doing this. You weren’t letting a merman kiss you in a creepy ass cave.

His body felt slightly cooler than your overheated one, his tongue sliding smoothly across your lip as though he knew you, as though he knew exactly how to kiss you. Every stroke of his lips and tongue was perfection, making you tremble against his strong body and try to grapple with your sanity as you tugged his hair, trying to somehow pull him closer.

Like him, his kiss was intense and all consuming – as though he was making damn sure you didn’t go home and forget him. It was almost like he was claiming you and reminding you that you belonged to him.

You weren’t sure what was happening, but you continued moving your lips against his, gasping in his mouth and pressing against his hard chest. You breathed heavily when he broke from your swollen lips, moving his hungrily down your neck. Your breath caught as he nudged the necklace with his nose, a low growl sounding in his chest. He nipped your neck with his teeth, a deep, husky word leaving his lips.

“Mine.”

You swore you felt some kind of bulge against your abdomen, confusing you for moments under all your lust as you gripped his hair. He ran his tongue up your neck, tasting your skin possessively.

“Y/N!”

Your stepfathers voice sounded closer now as you looked towards the entrance of the cave, seeing shadows.

Katsuki pulled away from your neck, and you took notice that his breathing seemed a little strained, and his jaw was tight.

It was clear that he didn’t want to let you go.

His nostrils flared with a huff, his bright, red eyes staring into yours.

“Soon,” he whispered in a low voice, his hand running up your bare back, his fingers toying with the strap of your bikini top as his expression turned serious. “I will watch – keep you safe,” he said slowly, making your heart punch your rib cage. His fingers came up to your collarbone, running them across the necklace with a satisfied look on his face. Your breathing was shallow as he lightly ran them down to your cleavage, a shiver running down your spine when he traced his fingers across the tops of your breasts. He looked hungry, like you were a present he couldn’t wait to unwrap.

A devious smile curled his lips, his fangs gleaming as he looked rather pleased with himself at your flustered appearance. He glanced back towards the entrance, seeing flashlights as he looked back at you once more, his eyes lingering on your face before he dove into the water. You barely saw the end of his tail, the orange and black a mere flash since he was so quick.

“Y/N!” Your stepfathers voice called again.

You sighed, trying to catch your breath. “I’M HERE!” You forced yourself to call out, your mind spinning and unable to process the fact that maybe, just maybe…you’d unwittingly bound yourself to an intense, admittedly handsome…merman.