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Katsuki let out a dramatic sigh as he slumped against his favorite sunbathing rock. Bubbles escaped his mouth and through his gills as he sunk deeper into his pillowed arms. His patterned orange, black, and white tail swished behind him lazily but twitched in annoyance as he continued to brood.
He came to a sudden, annoying, and fucking troublesome thought which brought him to this secluded spot. It hadn’t been long since the incident but the involuntary thoughts made his eye twitch - although it was barely even an event. They weren’t doing anything different. He was tolerating the presence of his rag-tag pod. They were all being stupid while Katsuki had to do damage control - the norm.
As Katsuki was wrestling an octopus off Denki’s face, he heard it. He wished he didn’t. He wished he just continued to call his so-called friends dumb and move on with his life. But he heard it. And it changed everything.
Just thinking about it made Katuski’s face erupt in heat.
“Fuckin’ - just hold still, Spark Plug!” Katsuki yelled as he chased down the eel merman.
“MMMF!” Denki yelled as he tried to pry the tentacles off his face.
The rest of the pod encircled them - pointing and laughing. Fucking useless.
Katsuki eventually caught Denki in a chokehold and wrapped his tail around the eel to keep him from thrashing. With the little patience he had left, he began trying to prod the creature from Denki’s now red face. The eel mer let out pathetic whines as the suction cups popped off his face - only for some of them to reattach to another part of his exposed skin.
The laughter didn’t die down for a second behind him - the annoying pricks. But one laugh in particular cut through the rest. It was a deep rumble that cackled with the rest of them. It sounded so damn jovial but it didn’t outright irritate the koi mermaid. Katsuki could feel those laughter reverberations in his soul - who the fuck was that?
Feigning annoyance, but mostly curious who the fuck that was, he turned his head and scolded, “Shut the fuck up!”
His eyes caught the usual suspects. Hanta’s tail flicked wildly as he laughed and Mina couldn’t control her high-pitched giggles. The pink beta mermaid hung off the sea bass merman for dear life as both had tears in their eyes. That deep laugh wasn’t coming from either of those chuckle fucks, but his eyes shifted over to the shark merman, and that’s when his brain stopped working.
Eijirou had his head thrown back and laughed just as heartily as the others. He’s heard the shark laugh before - several times a day. So what was so different? Why was Katsuki just noticing how beautiful that laugh sounded? As he stared, he couldn’t help but also notice Eijirou’s teeth. They looked so damn threatening all the time but when he was smiling so wide they looked… cute? How could dagger-like teeth look cute?! Then Katsuki’s eyes drifted to his shoulders, bouncing with each giggle. The koi mer noted how the shark’s gear tattoos on the joints highlighted his muscle definition. Was the other mer always that muscular? Were his shoulders always that broad? Eijirou’s size should’ve been intimidating, not alluring!
Katsuki’s mind bounced from one intrusive thought to the next, all revolving around the red-haired shark. It was new. It was new and weird and not like Bakugou-fucking-Katsuki at all!
Irritatingly, he could feel his face heat up to the roots of his hair. The octopus was still stuck on Denki’s face but he didn’t care. As they were all still laughing, Katsuki darted off. He needed to assess what the fuck was going on with his brain and his heart. Why was it beating so damn fast? Something must be wrong with him.
Definitely.
As the koi mer recalled that event from a few days ago, his face heated up the same way and his heart threatened to beat out of his chest. Again. Anytime Katsuki thinks back, he feels the same way - his body reacts the same way.
The mer wasn’t stupid. If these thoughts haven’t gone away - in fact, some nights they got worse and far more graphic than Katsuki didn’t think he was capable of - then that only means one thing.
He liked Eijirou.
God fucking damn it! He liked Eijirou!
Thinking it alone made his palms tingle and his muscles tense. He’s… he’s never liked anyone before. For a while, he thought he was incapable and comfortable being mateless forever. But this changed things.
He liked Eijirou.
Fucking hell! He liked Eijirou!
He was Bakugou Katsuki, the damn strongest koi mer in all the seas. How could someone as strong as him be paralyzed by a mere memory?! He clenched his fists - feeling his claws slowly dig into his skin. He was going to get nowhere by just sitting on this stupid rock. He needed to act. He needed to do something. His eyes narrowed as he stared off to the middle distance and came to an internal agreement.
If he liked Eijirou (Ugh! He liked Eijirou!) then he was going to get that dumb shark to fall head over heels for Katsuki, whether the fucker liked it or not!
---
The koi mer didn’t do courting. He didn’t have crushes. He didn’t like anyone! This was new. But it wasn’t impossible for him. He knows how to court, but this will be his first time doing it. And if he’s going to court Eijirou, he’s going to be the fucking best at it.
Going over the different rituals in his mind, Katuski decided to start simple: leaving gifts.
Kois would find the prettiest rocks and leave them at the den’s entrance of the one they were courting. Sure Katsuki could find a pretty rock, no problem. But why find a rock when Katuski could find gems?
Using his sharpened claws, Katsuki dug into stone and cliffsides for the shiniest geodes he could unearth. It was difficult and left his hands raw, but it was worth it to see the radiant purples, reds, and ambers gathered in his palm. He admired the shine as streams of sunlight bounced off them in a small spectacular rainbow around him.
They were perfect and definitely better than some dumb rocks.
Hell yeah, he was going to be the best at dumb-fuck-courting!
Katsuki’s powerful tail cut through the water leaving a wake of bubbles behind him. He did his best to be as loud as he could as he swam toward Eijirou’s den. As he predicted, the mer was digging around in the cave but didn’t notice Katsuki. The koi mer could hear the shark muttering to himself as he fiddled with something too. The hell was he doing? Doesn't matter - Katsuki had a mission.
Again, trying to be as loud as possible, the mer set down the geodes and made sure to swish his tail around. A torrent of loud bubbles swirled around Katuki which definitely caught Eijirou’s attention. His head whipped around right as the other mer set down the geodes. Katsuki made sure to hold eye contact as the last gem floated to the ground at the entrance of the shark’s den.
But as soon as the geodes were placed, he darted away.
Katsuki could hear Eijirou call out to him but the mer didn’t stop until the other’s den was a speck in the distance.
Mission complete! And a pretty damn successful one at that! There’s no way that tooth-for-brains fucker wouldn’t fall for him now!
---
Katsuki didn’t know whether to burst into tears or punch Eijirou in the face. Probably punch him in the face with how fast his blood was boiling. It hasn’t even been a full day since he dropped off his gifts to the shark, only for the mer to find him and present him with…
“What the hell is this?” Katuski asked as he held the item by his claws.
“It-it’s a necklace!” Eijirou stuttered as a blush crept up his face.
The shark scratched the back of his head as he explained where he got every piece that was either strung through or tied to the thin rope. His jabbering faded to the background as Katsuki inspected the necklace further. It was an odd piece that didn’t have any matching elements. It was so random - even if Eijirou was currently explaining the reasoning behind each item. There was a sharp yellow-ish rock, one of the fucker’s shark teeth, a coral that looked like the orange scaled “X” on his tail, and (lo and behold) the gems he gifted Eijirou.
“What the fuck, Ei?” the mer growled.
“Huh?” Eijirou said with a tilt of his head. Fuck him, that was cute. How dare he be adorable when Katsuki was fuming?
“I gave you these gems yesterday, you prick!” he yelled with a roll of his eyes. Did he have to spell it out for this dumb shark or what?
“Ye-yeah. Yeah! They’re really pretty! Thank you for bringing them - for the necklace!”
Katsuki’s eye twitched.
Why did he have to like such a moron?! Who regifts something let alone a courting gift? Katsuki couldn’t tell if Eijirou was being dense, an asshole, or both.
But as he stared down at the necklace in his palm, he felt his eyes sting. It may be on a piece of rope, but Eijirou still returned Katsuki’s courting gift. He gave it back, so does that mean the shark rejected him? Well, as dumb as it is, he did make this necklace. It was nice. But fuck him anyways. Those were Katsuki’s gifts to Eijirou!
With no warning in his body language or facial expression, Katsuki’s rage exploded. He punched the shark in the face. Eijirou grunted and floated back a few inches. He grabbed for his cheek, rubbing it as he yelled, “OW! What was that for?”
“For being an asshole!” Katsuki screamed back.
Anger still fueling him, the koi mer ripped the necklace in half, collected the geodes, and threw them at the shark.
“Those were for you. Not me. If you hate them so damn much then you can throw them away, set ‘em on fire, I don’t give a shit. Just don’t give ‘em back to me, teeth for brains!”
With a final huff, Katsuki jetted away leaving the shark with an expression of confusion and guilt. Good. The motherfucker should be guilty!
---
For some reason Katsuki let Eijirou swim up to him without biting his head off. He had a few days to calm down, but his eyes still narrowed at the shark as he approached. But seeing Eijirou push forward with his powerful tail that had a few badass scars on it and his beautiful hair flowing like radiant lava made his heart rate spike.
“Hey, Kat,” Eijirou greeted, carefully, “Hooow are you?”
“What is it?”
“Heh, straight to the point. Real manly,” the shark said under his breath. He shook his head and refocused, asking the other mer, “I was wondering… um if you would like to eat together? Sometime! Doesn't have to be right now! Don’t worry! Wouldn’t want to spring that up on you randomly. But do you want to grab a bite… with me?”
Katsuki was taken aback. He wasn’t expecting that at all. He thought Eijirou would give a half-assed apology that he would probably reject (yet he’d continue to court), but to get something to eat together? What did that mean exactly? Did he want them to hunt together? Well, Katsuki can catch his own food with no help from any extra - thank you very much. But was that even what Eijirou was talking about?
Not knowing how to handle this situation, the mer said, “I was actually gonna go hunt for my lunch now so…” Katsuki’s voice trailed off as he tried to back away - confusion clear on his face.
“Oh, that’s perfect! We can go hunting together! I can catch you some fish, we can eat together, and -”
“Ex-fucking-scuse me?! You hunt for me?!”
Eijirou’s eyes darted around as if the shark didn’t know what he did wrong. Ugh, the big loaf probably didn’t based on his expression. Stupid, dumb, cute, fucker!
“Uh… yeah?” he said, shrinking away in fear, “I mean… you left those gems but also gave them back. And I’ve been getting this vibe from you for a while, so I sorta thought that you’d like to… go hunting with me?”
Katsuki blinked. “What the hell are you talking about? If you’re insinuating that I let another mer hunt for me, you’re crazier than I thought. I ain’t no fuckin’ weakling! I hunt for myself.”
The koi mer huffed and turned tail to begin looking for lunch. The sad, sparkling eyes Eijirou gave him tugged at his heartstrings, but he stood by his word. He was strong. He didn’t need anyone to coddle him. Even if the help was coming from big, beautiful, dumb Eijirou.
But as he swam further and further away, he began to miss the shark’s presence. They hardly spoke since the necklace incident - of which he still kept the article specially hung in his den - and he was storming away again. Yet his heart continued to flutter a mile a minute. Thinking about Eijirou made the corners of his mouth threaten to quirk up.
He mentally slapped himself for not giving up on courting the shark. He was being a jackass recently, but for some reason that didn’t deter Katsuki.
It should’ve. But it didn’t.
---
The koi mer mentally went over the courting rituals again. He didn’t want to jump to step three - it seemed a bit much even for him - but step two was embarrassing as fuck. Katsuki knows that dancing is common. Hell, he’s seen his parents do it plenty of times around his childhood den. Seeing the two circle each other made him want to barf with how soft the act was.
But if Katsuki was going to make the shark mer accept his courting, then he had to fucking do it he guessed.
The sun set hours ago and the ocean was lit with the silver light of the moon. Most other mers were asleep by now but Katsuki was certain the shark would still be active enough for his plan.
The koi mer didn’t have to venture far before he saw Eijirou talking to some other sharks he didn’t know and didn’t care about. His eyes were zeroed in on red flowing hair and adorably sharp teeth. He heard that deep rumble of a laugh even from this distance.
Wonder what it’d be like to lay on top of him as he laughed. Bet I could feel it in my bones.
Fucking hell! Focus!
He swam up right as the other sharks were leaving. Eijirou waved them goodbye, and when he turned his face lit up as he saw Katsuki.
“Hey, man!” Eijirou smiled. The past events seemed to catch up with Eijirou as his smile faltered and was replaced with a bashful wobbly lip. “Uh. I’m sorry for the other day. I guess I got some signals mixed up and I don’t want things to be awkward between us or anything.”
Katsuki quirked a brow and rolled his eyes. “What’re you talkin’ about? Don’t stress yourself thinkin’ about stuff like that. No apology needed, dumbass.”
Tension dropped from tattooed shoulders and he sighed with a smile on his lips. “Oh… well that’s a relief. Thanks, man!”
Katsuki didn’t know what Eijirou was talking about - truly - but it was worth the little lie of omission to see that beautifully dangerous smile.
“But did you need something, Kat? You’re not normally awake this late.”
The koi mer tried to control his heartbeat thinking how well Eijirou knew him. Knew him well enough that he wasn’t a night mer and liked to sleep early. Would the shark sleep early with him? He hoped so.
Ugh! Focus. Focus!
“I…” Katsuki faltered. Pink tinting his cheeks, he cleared his throat and focused his brain. “Wanna go on a swim?”
Somehow, the shark’s smile grew and practically glowed in the moonlight. “I’d love to!”
With a nod of his head, the two mermen ventured out into the open ocean. The moonlight did well to light the open ocean, but it was still dark and serine. No one else was out making the endless silence around them feel wide - yet they were able to fill the space with their easy conversations. They talked and talked, and it was easy. It was surprising how easy it was when Katsuki just ignored his raging heart and went back to being Eijirou’s best friend. It almost felt like nothing was wrong. It felt like they were just two mers hanging out. Laughing at dumb jokes and playfully pushing one another. It was… nice. It was normal.
“I can’t believe you like that shit!” Katsuki laughed.
“I can’t believe you’re so picky!” Eijirou shot back with a wide grin on his face too. “With all the calories I need, I can’t afford to be choosy.”
“But to eat an eel?” he balked, “I’d feel too much like I’m eatin’ Spark Plug.”
Eijirou’s face dropped dramatically. “Oh, gods! Why’d you say that, Kat? Now that’s all I’m gonna think about when I eat eel!”
“Then don’t eat it. Simple.”
“Noooo! It actually tastes pretty good!”
“Yecch!”
They both laughed - Eijirou much louder and deeper than Katsuki - and it was nice. It was nice to laugh like this with his closest friend.
But hopefully, Eijirou won’t remain just a friend for long.
Smile still on his face, Katsuki pushed ahead - only a tail's length away. Executing his plan, he twirled as he swam forward. His long, thin fins hypnotically danced as he made gentle corkscrews. His smile turned soft yet confident as he turned toward Eijirou, who was just staring at him - eyes wide and unblinking. Arms stretched over his head, he slowly dove back towards the shark. He made a point to wave his tail in a way that made his fins flow in the gentle ocean current - splayed in grace to see all his speckled colors. He did that a few more times. Spinning, circling, dancing, yet the shark didn’t move to dance with him.
After a few moments, Eijirou let out a small chuckle and said with a confused brow, “What are you doing?”
Katsuki froze.
What did Eijirou mean ‘what was he doing’? Wasn’t it obvious?! He was dancing! He was dancing, right? Was he doing it wrong? Was he not graceful enough? He’s not used to this shit but he wasn’t that bad! Right? Was he so bad that Eijirou didn’t like it? Was he so bad that Eijirou didn’t even know what he was doing? Or maybe he just didn’t like Katsuki’s dancing. Was that it? Did Eijirou not like his dancing? Didn’t like him?
Fuck. Fucking fuck!
The koi mer’s eyes began to sting. He clenched his jaw and dug his claws into his palms. This was a mistake. He should’ve never done this. He could’ve asked for some fucking advice instead of making an ass of himself.
“Fuckin… whatever,” the koi mer muttered under his breath.
Before any tears could fall, Katsuki turned and began to dart away. He wanted to crawl into his den and hide until the sun exploded, but the other’s webbed hand caught his.
“Whoa! Katsuki! Where’re you going?”
“Away!”
The shark gave a frustrated growl as he pulled Katsuki towards him and forced the koi to face him. “Not this time! You keep running away before I can even ask what’s wrong.”
“‘M not running away!” the other mer growled.
“You just yelled you were going away!”
“‘M goin’ away, not runnin’ away! There’s a difference!”
“Oh, is there Kat? Every time you get that look on your face you swim like you’ve been burned. Look, I’m sorry. I didn’t mean to make you mad. But can you please tell me why you’re mad so I don’t do it again?”
Katsuki froze. He couldn’t meet those scarred, brilliant eyes that felt like they were boring into his soul. It was such an honest look that made his core tight. He should return it in kind, but fuck if that wasn’t difficult. If only his tongue didn’t feel like it was swelling in his mouth. If only it didn’t feel like his ribcage was trying to claw to his throat and cut his vocal cords.
He should say something. But what the hell is he supposed to say without it sounding like the cheesiest, most embarrassing crap?
Fangs gnawing at his lower lip, Katsuki mumbled, “I was tryin’ to dance with you.”
Eijirou tilted his head. “What’s that?”
That got the koi mer’s attention. It wasn’t ‘Oh, that’s what you’re doing.’ or ‘Well, you were bad at it.’ Eijirou asked the question like he’d never even heard of the concept before. His eyes snapped to the shark’s, baffled. “Wha - dancing. Ya know… dancing!”
“You repeating it won’t make me understand what it is, Kat.”
His jaw hung open. “How do you not know what dancing is, teeth for brains!?”
“Come on man, you can’t yell at a mer for not knowing something! Is that a koi thing maybe?”
Katsuki was about to rip him a new one when he paused. A koi thing. Was it really just a koi-mer ritual?
“Wait,” he said, putting some distance between the two so he could put the puzzle pieces in his mind together. “You really don’t know what dancing is?”
“No. Is it important?”
“Kinda! It… ugh. It’s a thing you do when two mers swim around each other because...”
“Like what you were just doing?”
“Yeah.”
Eijirou smiled. “It was really pretty. But why’d you do it?”
Katsuki’s face was on fire. He was glad for the veil of night or else Eijirou would’ve thought he was sunburned.
“It’s… a thing… for… courting,” he said timidly. But the sound of his voice so soft made his own blood pressure rise in irritation. That tone didn’t belong on his crass tongue. “It’s for courting, alright? A-and I tried to dance with you, you stupid fuck! I’ve been trying to court your dumb ass for a while now and you’re not fucking getting it! But… damn it, is dancing really just a koi thing? Fuck!”
Eijirou blinked as Katsuki simmered down from his explosion. The koi began to pace, too focused on his racing thoughts and the deafening silence between the two. Eijirou was so quiet that the other mer was about ready to swim away again, but the shark whispered with a growing grin on his face, “You’re trying to court me?”
“Yeah! And you either hate me or don’t get it!”
“It’s definitely the second one!” Eijirou rushed out. “Definitely! I didn’t know! You were - you were courting me, Katsuki?”
He crossed his arms over his chest and shrank into himself a bit. “Yeah? And?”
Eijirou chuckled. The rumble in his chest reverberated and sent a pleasant chill up Katsuki’s spine. “I don’t hate you. Definitely don’t hate you. I actually thought you hated me 'cause I’ve been trying to court you too.”
Katsuki’s eyes grew wide. “What?!”
With a sheepish grin, he scratched the back of his head as he explained, “Yeah. When you dropped off those gems, I was already making you the courting necklace. Sometimes, for sharks, the other can give gifts for the courting necklace. Which is what I thought you did. But you didn’t know that, huh?”
“No, Ei! It’s a courting ritual for koi to give nice rocks or some shit. So when you gave those gems back I thought you were spitting in my face!”
“Absolutely not! Oh gods, no wonder you swam off so mad. And - but what about the time I asked you to eat with me?”
Katsuki rolled his eyes. “That one I thought you were just being an ass and saying I couldn’t hunt for myself.”
“What? Oh, hell no! I know you’re the best hunter in our entire pod! Hell, probably the entire ocean!” Katsuki could feel his pride swell but he kept his mouth shut for Eijirou to continue. “A shark courting ritual is to go hunting with the one you’re courting and then ‘feast upon our victory in a successful hunt together!’ I was… I was trying to do that.”
The koi mer scoffed, “Huh… Fucking hell. We’ve got some weird ass rituals.”
The shark chuckled, “Yeah… I guess we should’ve explained ourselves, huh?”
Katsuki didn’t answer but tightened the arms over his chest. His brow furrowed as he processed everything. So he was courting Eijirou. Big, beautiful, dumb Eijirou. And he was courting Katsuki back. They were courting each other. Yet heat still simmered on his skin. The thought of the shark not recuperating in his rituals stung. But he didn’t recuperate in Eijirou’s either.
Ugh. Eijirou was a dumbass. He was a dumbass.
Breaking the tense silence, Katsuki muttered, “Sorry or whatever… for - yeah…”
A kind smile spread on the shark’s lips. He swam a bit closer to the koi and carefully reached out. “It’s okay. I’m sorry too. But… if we were courting each other, do you - I don’t know if you want to finish all the rituals, but do you just want to skip it and just start dating?”
Katsuki looked into those ruby-like eyes. He scoffed again and shook his head in disbelief. God, how did this fucker know him so well?
The koi mer cackled and tugged the shark close. He subconsciously wrapped his tail around smooth skin as he said with an easy, mischievous smile, “You fuckin’ read my mind, Ei. ‘Sides, I don’t wanna do the last courting ritual anyway.”
Eijirou laughed - his shoulders bounced and he threw his head back as the deep rumble reverberated around him. With a giggle still on his lips, he pulled Katsuki in and hugged him as he laughed.
Katsuki was right, it was nice to have his head on the shark’s chest as he laughed.
---
“By the way, what was that last koi ritual?”
“Fuck first ask questions later.”
Eijirou chokes on his spit.