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The ocean has always been a beautiful place, full of colorful and vibrant life. Sharp, soft and mysterious. Beneath the waves, millions of lifeforms flourished. But none more fantastic than the merfolk.
The Calder Reef lay well hidden in the furthest reaches of the sea, far away from any source of land. The Reef thrived in the clear waters, creating their own culture and customs. History and family trees.
Even if they never interacted, the Mers lived very similarly to humans. They lived together in family pods, weaned their young and and fell in love.
Katsuki has spent years courting Izuku; catching him fresh fish to prove that he could provide for him, gifting him polished rocks that shimmered in the light and lastly crafting him a special betrothal gift. A shell necklace, weaved together with corded seaweed and hand crafted beads.
Izuku wore it proudly, a show to everyone that they were set to be mated. The betrothal was celebrated by the entire Pod, so fierce, that it shook up the sea. Creating waves that make it feel like even the water was happy for them.
Their union was a long time coming since they had known each other since they were guppies. Swimming circles around their mothers and driving them crazy side by side; their entire lives together. There was no Katsuki without Izuku, there was no Izuku without Katsuki.
Even if they couldn’t conceive guppies of their own, they were content with their small family. Incredibly happy!
Katsuki was a lionfish Mer; his tail was vibrantly orange and white striped. Hints of black lined the edges, with beautiful fans and deadly toxic spines that flowed as he swam.
He wasn’t the largest of the Mers in the Pod, but he was easily considered one of the most dangerous.
Izuku was a mandarin fish Mer; his tail lacked scales, but instead was completely smooth and silky. It swirled with dark and electric greens, adding just the slightest hint of red highlight.
The smooth coating mandarin fish tails that can be poisonous to open wounds, which is a great defensive tactic. Though it isn’t incredibly helpful when he is so small, mandarish fish Mers are usually smaller than average.
Every Merfolk had a spot in the Pod, tasks they did to help their community grow and flourish. Everyone looked out for each other, helped where they could and wore multiple hats. A lot of the time it would depend on the skillset they were born with, which type of fish genetics.
Predator Mer were more skilled at hunting, while prey Mers were more adept at building homes or making nests. But it was never dependent on that, any Mer could choose what they wanted to do as long as they proved themselves.
Which was why, even though Izuku was too small to technically be considered a predator Mer, he was still allowed to patrol with Katsuki. Because he was skilled and used his toxic tail to his advantage.
Meanwhile, Katsuki was a skilled hunter, his spines were sharp, toxic and precise. He was deadly and fierce in combat. But always gentle with Izuku. Always.
“Kacchan look at this one!” Izuku popped his head out of the cramped space between the corals and held out a large clam shell.
“Oh, that's a big one.” Katsuki praised with a gentle smile that only Izuku ever got to see. It spread easily upon his features since no one else was around. “Nice find, Bubbles.”
Katsuki took the clam and broke it open with his sharp claws and they shared the flavor together.
Izuku loved hunting for clams for Katsuki, since the larger Mer could not fit in the crevasse between the corals, but Izuku could. He weaved easily under the massive rocks and natural tunnels, finding the best meals for them to share.
“This one looks like a manilla clam.” Izuku examined the shell between his fingers. “Oblong shape and it has that crosshatch pattern of ridges. The shell is gray and brown with a ridged pattern. The inside is definitely yellowish and it has that splash of dark purple near the hinge.”
“Yeah, we get it! it’s a manilla clam, just eat the damn thing.” Katsuki rolled his eyes.
That was why Katsuki called him Bubbles, because of the constant stream of bubbles that exited his mouth when he muttered.
Technically, they were on patrol together. Watching for predators, but it was easy to get distracted when hardly anything ever happened. Of course, they were not slacking in their duties. Mer had heightened senses, they could smell for miles and their fins felt the change of currents around them.
Izuku stuck his tongue out to Katsuki in a tease. “Make me.”
The Lionfish Mer gawked and charged for him. “Oh, you asked for it.”
Izuku giggled and ducked back into the corals, he knew Katsuki wouldn't fit inside, but he could still reach him and pull him out.
“Get back here, you slippery bitch!”
The chase was one, one that they had done dozens of times before and loved every time. It leaned into their instincts, lit up their senses and made them feel extra alive.
The sound of laughter filled the edge of the reef, bubbles swirling around as Katsuki chased Izuku through the corals. Just to taunt him, Izuku would poke his head up every once in a while and chant.
“Over here.”
“Are you even trying?”
“Come on, you can do better than that.”
Izuku loved teasing his future mate and seeing how his face grew red with embarrassment and rage. Eventually, Katsuki would always catch him, which was actually Izuku's favorite part.
“Gottcha!” The lionfish managed to grasp Izuku’s arm and yank him into the open.
He was forcefully trapped into a tight embrace while Katsuki covered every inch of him with harsh kisses.
“How. Dare. You. Run. From. Me!” Between each word, a mushy kiss was placed over his skin.
“Kacchan~” Izuku could not control his laughter as they spun around.
“Kiss me.” He demanded and Izuku was powerless to say no.
Their lips met between smiles, familiar skin upon skin as they kissed simply. They had kissed dozens, hundreds of times and yet they never grew tired of it.
It was perfect, not because they were perfect, but because it was them.
They both came to their senses and noticed the extra presence nearby at the same time, their adrenaline spiking. The scent of a tiger shark floated close by, too close.
If they had not been distracted, they would have noticed it much earlier.
“Fuck.” Katsuki cursed, his gaze looking behind Izuku.
He turned and saw it, a massive striped tiger shark loomed directly behind them just beyond the drop off of the reef. Staring directly at them from about ten meters away.
Fuck was right.
They were too far away from any means of proper protection, since the shark’s powerful tail could out swim them in seconds. The only hope of survival was to fight back, thankfully it would not be their first fight with a shark and probably not the last.
As long as they worked together, they could tire it out and send it away. The shark may be faster, but they could turn sharper. As long as they stayed to the side of its jaws, they should be fine.
With one quick second to make eye contact, Katsuki and Izuku jumped into action first. They charged into the open water, heading straight for it and took to each side of the shark.
Izuku used the swirled pattern on his tail to mesmerize the shark and confuse him, disorienting him just enough where Katsuki could shove him into a new direction. Away from the Reef, away from their friends and family.
When the shark retaliated, Katsuki flashed his spines in a wave motion; an incredibly effective intimidation tactic that usually sent even the largest of predators packing. However, this shark did not back down, instead it grew angry.
The tiger shark swamped its massive jaws at Katsuki and he barely evaded it in time, the sound of its powerful teeth inches from Katsuki’s tail.
It seemed like their usual tactics were not working on this creature and it was not afraid of them; the shark was playing with them.
An unsettling sense of fear crept into Izuku’s mind, worry for Katsuki’s safety. They were no where close to help if he got hurt.
Izuku’s moment of distraction proved fatal, because the tiger shark closed in on him. Unable to twist out of the way quick enough, Izuku's tail was caught between layers of jagged teeth.
Pain erupted viciously below his hip as he was shaken violently, a cry escaping his lips from the agony. A film of blood floated from the wound and surrounded him, making it hard to see.
“Izuku!” Katsuki roared in anger and fear, jumping on top of the shark with his claws beared.
Both of them scratched and bit the shark’s thick skin, but his grip was solid, wanting to enjoy his meal. Izuku sobbed again when the teeth ground together against his flesh, feeling the teeth hitting bone.
His blood swirled around them even more, which would attract more sharks. They needed to get out of there and fast, or they’d be swarmed by more predators.
As a last measure, Katsuki ripped out one of his spines, making himself bleed and stabbed the shark with the venomous spike. The shark's skin was too thick to penetrate properly, so it would not be enough to kill, but to stun.
The tiger shark reacted immediately and unlocked its jaw, dropping Izuku. It swam away, for the moment.
All the strength had been zapped from his body and his tail was roughly mangled, unable to swim; he started sinking. He couldn’t even keep his eyes open. Blood seeped from his body as he slowly lowered down the drop off and into the darker waters below.
“It’s alright, I’ve got ya.” Gentle hands caught him as Katsuki lifted him back to the reef. He swam them back to the sunlight and carefully tucked Izuku into the tunnels of coral. “There, stay hidden.”
“K-Kacch-an.” He felt so tired, probably from blood loss.
“This coral is not strong enough to stop it.” Katsuki looked around, panic in his eyes. They both knew that no coral would stop a shark from getting its fresh meal. Especially a downed, bleeding mermaid. Ripe for the taking, Izuku was a sitting duck.
Katsuki wouldn’t be able to swim fast enough to carry them both to safety and no one else was around to help. They were on their own.
“Hurry, it’s going to come back. Run and hide.”
Katsuki could flee and the scent of Izuku's blood would draw the shark to him instead, even if he couldn't swim, he could at least save his love.
“No! You do not die today!” He roughly growled.
“There is no other option, I can’t swim!” Izuku begged now, pleading for Katsuki to save himself.
He saw the horrible moment of realization hi Katsuki, his expression relaxed and his eyes widened.
“But I can.”
With one look, Izuku could tell exactly what he was thinking.
“No.” He lowered his voice, trying to sound as threatening as possible, even though he was deeply in pain. “Don’t you dare.”
“Izuku, I refuse to let you die.”
No no no no no! This was not happening!
“Kacchan no!”
“I love you so much, you are my ocean, my life.” Foamy tears sprouted from the corners of his red eyes. This wasn’t supposed to happen, Katsuki doesn’t cry.
Izuku could see the shark starting his approach again, rounding in on them from behind Katsuki’s back. He had to run! Flee to safety!
“No! Let me save you, run away. Please!” They were both crying now.
“There’s nothing I wouldn’t do to keep you safe.”
Gentle hands skimmed his jaw as they left his face, Katsuki’s form turning around and facing the shark head on by himself. Bubbles whirling behind him as he sped forwards at full speed towards the predator, leading it away from Izuku.
“NOOO!” Izuku shrieked, his voice tearing itself apart as he tried to escape the coral and catch his love. But his tail was so mangled and the coral that Katsuki chose, too tight and locked him in.
He could only watch as the tiger shark snapped its jaws, while the lionfish Mer dodged with impressive agility. Katsuki was able to keep out of its grasp long enough to draw it far away into the distance, which made it hard for Izuku to see.
But eventually, he knew Katsuki would tire and run out of luck. Reef Mers were not made for the vastness of the open water.
Sure enough, a cloud of red bloomed around Katsuki’s torso and shoulder. Even from far away, Izuku could see the spurts of his lover's blood dye the water.
“Kacchan!!” Izuku’s vocal cords vibrated intensely as he cried, his siren-like wail traveling through the water.
The shark gnawed on Katsuki's body again, making him flinch, but Izuku knew it was over. The murky red grew stronger as the shark swam away with his catch, further from the reef, away from Izuku. Taking Katsuki’s body from him.
Izuku never even got to say goodbye.
Shaking and convulsing with emotion, Izuku wept bitterly; mourning the loss of his beloved. His body was exhausted, still continuously bleeding from a severe wound. If left untreated, he would bleed out. Or attract more hungry sharks.
Maybe dying wouldn't be so bad? Then he could see Katsuki again and they could swim side by side together forever.
With that thought on his mind, Izuku stopped fighting to keep his eyes open and allowed unconsciousness to take over.
************
It was still early when Shouta heard the cry, the guttural wail rode through the current and altered everyone within the Reef. It was a sound of pain and sorrow.
Immediately, he knew that someone was in trouble and he jumped into action to help. As an octopus Mer, he had many capable hands and always aided when he could.
Quickly zipping through the water, he swam as fast as he could towards the source of the cry. On the way he ran into other predator Mers, also answering the call. But he could smell more than just Mers too.
There was blood in the water and where there was blood, there were sharks.
“Shouta, you heard it too?” His mate Hizashi, a parrotfish Mer, matched his speed.
“Who was that?” Shoto, the clownfish Mer appeared.
“It sounded like Izuku!” Uraraka, a squarespot anthias Mer stated. Panic in her voice.
“Izuku and Katsuki were on patrol today near the drop off.” Hizashi swam a bit faster, leading the group. “Follow me!”
They swam together as a Pod, quickly and efficiently trying to find where the scream had come from. Following the scent of blood, which proved difficult because it was thick and the currents were pushing it around. The drop off was a wide area and Izuku could be anywhere, he was a small Mer.
“There!” Shoto pointed into the coral bed, where he could see a plume of red floating up into the surrounding water. They all immediately swam towards it and at first they saw nothing but the blood, but Uraraka moved a coral out of the way to reveal freckled skin.
“Crustations! It is Izuku!” Hizashi cursed and moved in closer.
He looked terrible; his face was pale and tense. Even if he was completely comatose he looked like he was in a great deal of pain. Remnants of tear foam stuck to his eyelashes and one of his hands gripped his betrothal necklace tightly.
Blood was seeping through the cracks of the coral, too much of it, but where was it coming from? Aizawa positioned himself further down the length of Izuku’s body and found his tail, which caused his heart to clench.
“We need seaweed, now!” He demanded sharply and without hesitation, Uraraka retreated to find some.
Izuku’s tail was a remnant of what it once was, the smooth surface was ripped, torn and bitten apart roughly by what looked to be a large bite mark.
“Blue sharks approaching from the drop off.” Hizashi warned as he watched their backs. “We need to get him out of here.”
“We need to stop the bleeding, or he won’t make it back to the Reef.” Aizawa pressed his tentacles around the wound for now, but it would not hold forever. “Where is that damn seaweed?!”
“Here!” Uraraka swam up with handfuls of the lengthy green weed.
Aizawa rushed to grab some from her and shoved a piece of it into his mouth, then urged his Pod mates to do the same. “Chew but do not swallow.”
Once they chewed the seaweed into a soft concoction that mixed with their Mer saliva, they pressed the solution into the worst of Izuku’s wounds. He flinched at having his lacerations poked and prodded, but did not fight them.
A shadow passed overhead, the blue sharks getting bolder now as they circled above them.
“Time to go.” Aizawa finally urged.
“But, where is Katsuki?” Shoto looked around for his friend.
That was a good question that Aizawa hadn’t even thought of, since he was so focused on Izuku.
Where was the lionfish Mer? He was hardly ever separated from Izuku and they should have been on patrol together.
“We don’t have time to search for Katsuki now.” Hizashi made the decision. “He is a strong Mer and can take care of himself, we have to trust in him. In the meantime, Izuku is dying and more sharks are swarming this place by the minute. We must leave now."
The clownfish Mer didn’t seem to like it, but knew that he was right. “Okay.”
Carefully, they moved the coral aside and pulled Izuku’s body out of the crevasse. Aizawa used a few of his tentacles to carry Izuku gently, and the rest to propel him forwards.
“Uraraka, swim ahead of us and prepare Inko for our arrival. Have Recovery Girl meet us there with as many medical remedies as possible.”
“Yes Sir!” As the fastest swimmer, she easily bolted ahead of them.
They reached the safety of the Reef about ten minutes later and swam straight to Izuku’s mother cave. The mandarin fish Mermaid was already spinning in circles with worry, when they swan in and she saw the state of her son, her face paled drastically.
Foaming tears floating from her eyes, watching Izuku be laid upon his childhood bed. Bleeding and completely unresponsive.
“My baby.” She reached out and gripped his hand. Her lips trembling with emotion as she took in the state of him.
“Coming through! MOVE!” The harsh and urgent voice of Recovery Girl bellowed as she pushed her way into the small cave.
“Is he going to be alright?” Inko asked the moment Recovery situated herself by the bed.
“I haven’t even examined him yet!”
“Sorry.” Inko deflated. “I’m just worried, I haven’t seen him this hurt before.”
“I’m not going to lie, this looks bad. But a tail bite shouldn’t kill him.” Her hands hovered over the affected area. “But, I will need time and space to operate properly. Please.”
That was her polite queue for Inko to leave, which she seemed to understand. With a small, sad nod, the Mermaid left the room hesitantly.
Only then did Recovery Girl turn to Aizawa. “So, you found him at the drop off?”
“Yes.” He nodded. “It looks like a shark bite, but I couldn't identify the type.”
“The teeth notches point sideways.” She pulled out various items from her special bag of tricks and got to work. “Definitely a tiger shark.”
“Tiger shark…fuck.” Aizawa rolled his neck thinking about the pain Izuku had to endure.
“He should be fine though, thanks to your quick thinking with the seaweed, you were able to get the bleeding under control. With some physical therapy, he should be fine.”
They thought that was it, that everything would return to normal. That Katsuki would show up after the sharks vanished and rush to Izuku’s bedside.
However, several night cycles passed and no one knew where Katsuki was, no trace of him was found anywhere. They searched high and low for the lionfish Mer, but he had completely disappeared. Vanished.
Some believed that he was dead, killed by the same attack as Izuku. Others theorised that he dumped Izuku and ran away. The Bakugou family mourned the unknown, holding out hope that their son was somehow still alive out there. But no one knew for sure, no one except Izuku.
The mandarin fish Mer had yet to wake up after almost a week of sleeping and somehow he looked worse than before. His vibrant colors of green and red had faded to a dull shade of their former color. Pale and almost white.
His tail, fins and even his hair had lost their pigmentation, making Izuku look like a ghost. His skin was cold to the touch and he had shown zero signs of waking up.
“What is wrong with him? He is home, he should have woken up by now!” Inko cried.
Recovery Girl sighed and held Inko’s hands tightly. “I’m so sorry, we’ve done all we can. It’s all up to Izuku now. His wounds are mostly healed, but…”
“But what?”
Aizawa wasn’t sure he wanted to know the answer to that question either, sheerly based on the hesitant look upon Recovery Girl's face.
“For reasons we can’t explain, we’re losing him.”
“Losing him? Aizawa repeated with shock. “How?”
“It seems he’s lost the will to live.”
************
Fuck! Fuck! Fuck! Fuck! Fuck! Fuck!
Katsuki was going to kill this stupid shark, his entire torso felt like he was getting stung by a million jellyfish inside his stomach.
Jagged teeth sawing into his chest as the tiger shark swam further and further away from the Reef he called home. The plume of Izuku’s blood got smaller and smaller and he was dragged away. His heart aching at the thought of leaving his love behind, probably the last time he would ever see him again. The memory tarnished by both of their blood and tears.
But even if it was the last thing he saw, he could die a happy Mer. Katsuki knew the decision he made was most likely a one way trip. He saved his mate and he would never regret that! But fuck if it wasn’t painful!
Eventually Katsuki wanted to try and escape, but he couldn't yet. He had to wait until they were far enough away from the reef that the shark could not go after Izuku. His mate was badly hurt and wouldn’t be able to fight back or flee properly. However, it was almost impossible to gauge time when Katsuki's system was pumping adrenaline and he was losing blood fast.
The shark shook violently and swam at a faster speed than Katsuki had ever gone before, that mixed with the blood in the water; he was completely disoriented. He had no idea which direction was up, down or where they had come from.
Just a few more minutes, hang on a few more minutes. He told himself, demanding himself to stay conscious. Though his fingers started to tingle and his head pounded with a furious headache.
When he couldn't take it any longer, Katsuki forced his failing body to cooperate and collected several spines from his tail. Grouped them together in one fist and focused all his energy on his aim and strength.
With a roar, he plunged the venomous spikes into the tiger shark's eye.
The shark flinched violently and the pressure against Katsuki’s torso released with a sickening grind as the serrated teeth separated from his skin. Blood spewed from his mouth from the altercation, agony ripping across his body. But he was free.
He gasped out a cry of relief at the feeling of release and the possibility that he might actually survive. The idea that he could make it home! He made it past step one and he didn’t think he would actually make it to step two.
The tiger shark shook in a fit as if swam away from him, blood seeping from its eye. Face swelling from the poison, knowing not to mess with him anymore.
He floated there for a moment and allowed himself a second to catch his breath and assess his situation.
He thanked a higher power that his tail was unharmed, but his upper body was completely torn up. A crescent shaped bite mark looped over his shoulder and down his abdomen, his clavicle was most likely broken from the force. The wounds bled a lot and he would need something to patch himself up, but observing his surroundings, there was nothing.
He was in the open ocean, no sand, no reef, no seaweed; nothing. Just blue water all around him. No fish, no shark. He couldn't even see the bottom sandy floor, it was just…nothing.
His heart pounded, and he could actually see the blood leave his system faster. Fuck! He had to keep his panic under control. He could do this, he could find his way back home.
Izuku needed him, he was still injured and needed help! If he swam fast enough, Katsuki could make it back before they realised he was gone.
How happy Izuku would be to see him! Probably mad too. Katsuki imagined exactly how the interaction would flow.
He would show up to the Reef, banged up and bleeding. Izuku would see him from his seabed, patched up and held down by both their mothers as he screamed at Katsuki for acting so rash. Then he would cry those foaming tears that Katsuki loved to see when he got overly emotional.
Izuku would tell him that Katsuki is an idiot, but he loved him and that he was so happy that he was alive. Then it would all be alright.
He could see it so vividly, Katsuki needed that to happen. It’s what would happen, if he had any say about it!
But first, he needed to stop the bleeding, or else he would attract more predators. Since there was nothing else around for him to use, he was forced to use his own spines.
Katsuki hated using his own spines as steroids, but they worked in a pinch. Ripping them out himself always hurt like a bitch and he only had so many of them. They would grow back eventually, but it took a couple months.
In situations like these, it would jump start the healing process, not instantly, but it would give him the energy he would need to get home.
“Fuck it.” He ripped one of his eleven spines remaining and stuck into the deeper part of his wound, the seizure of pain almost caused him to vomit. But he was somehow able to keep his sanity.
Breathing heavily, he spun around and found the trail of his own blood. He needed to move fast, because the trail would not remain for long, ocean currents worked quickly. Soon, even the scent would disappear.
He twisted his body towards the trail and immediately his torso rejected the movement, this was going to be harder than he thought.
Obviously, he knew the ocean was massive, but never before did he come face to face with that reality. Katsuki seemed to swim for hours, endlessly, tirelessly and yet it didn’t seem like he was making any progress.
The only way he could tell that time was passing, was that the sun was setting and thank the heavens it was setting in the proper direction. Which meant he was traveling the right way.
But this was also a bad thing, because the ocean was a dangerous place at night and Katsuki did not have his own natural bioluminescence. Which meant he would be left completely in the dark, pitch black.
As a lionfish, he had excellent night vision, but only at close range. Which basically did him nothing in the vastness of the open ocean.
When the sun finally did set, he was forced to rely on only his sense of smell to track the scent of his own blood. But it was growing faint and the water was spreading it around, making it hard to detect. He needed to get back home before the trail went cold.
Katsuki shot himself with another spine and his senses heightened, his pupils blowing wide and his nostrils flaring.
He used the fresh energy to booth his speed and propel him through the dark water. Even if he was visually blind, the scent was pointing him in the proper direction.
Further and further he swam, until his fins started to ache but he did not stop.
Up ahead he saw something glow and he squinted his eyes to try and get a better look. It appeared to be a cloud of lights, which was strange and unnatural. But he could not alter his course, he could not lose the scent trail.
As he got closer, Katsuki’s heart dropped. A massive swarm of mauve stinger jellyfish. Their sizes varied drastically, some tiny and some absolutely massive, with tentacles as long as himself.
“Seriously?!” Out of all the places they would be, of all times! They had to situate themselves directly in front of where he had to go!
“Fuckin’ jellies!” He grumbled and pulled at his hair in frustration.
Mauve stinger jellyfish stings were known to be incredibly painful, but not life threatening. However, with this many of them…
The scent trail led straight through the bloom of jellies. Did Katsuki risk going around? Would he survive swimming through?
He shook out his hands and took a few deep breaths. “I can’t believe I’m doing this.”
With less speed and more precise agility, Katsuki did his best to weave through the cloud of jellyfish. There were hundreds of them! Above his head, under his tail and everywhere he looked. He had to make sure not to get turned around, lest he lose his sense of direction.
As he moved elegantly forwards, his tail swiped the side of a tentacle and suddenly, not just the affected area, but his entire body lit up as if he were on fire!
“Fuck!” He cursed, biting his lip and trying to conceal the pain, he couldn’t move around too much, lest he risk more stings.
A throbbing pulsated through his entire tail and caused his stomach to turn, but he forced himself forwards.
For Izuku.
He had to keep moving, he was still in danger.
Another brush against his arm sent him into a fit, which caused him to bump into another jelly and set off a chain reaction of pain. But he was able to calm himself down enough before true disaster struck.
For Izuku.
Just when he thought he was spinning in circles, he spotted a dark patch of ocean peaking out of the brightness of the glowing mauve stinger jellyfish cloud.
For Izuku!
With one last excruciating sting to his cheek, he pushed through and made it to the other side.
“Fuck you!” He turned around and cursed at them. “You can’t take me out, you brainless assholes!”
They may not have beaten him, but they did a good job at trying, because he was in bad shape. He’d been stung multiple times and his vision started to spin.
“...F-Fuc-ck y-you…” Katsuki lurched forwards and upchucked what was in his stomach, the murk of it sinking to the deep unknown.
He needed rest, he needed medical attention. He needed his mate. But none of that was nearby, it was all at the Reef, at home.
Home, Katsuki! Get home! With a heavy grunt, he stabbed himself with another spine and pushed himself forwards again.
************
It was hard to keep track of time, because Katsuki was sure that he was losing his sanity. He was alone, hungry and hadn’t slept in the many moon cycles that passed. He hadn’t been keeping track.
He didn’t see the point anymore, he’d lost the trail home days ago and was utterly lost. Everything looked the same, there was nothing for him to use as landmarks.
After days of nothing to eat and being beaten by the obstacles of the Ocean, Katsuki’s body could barely swim anymore.
His body was void of all strength and resolve, now he just floated halfway between the surface and whatever lurked below. He could feel the sun beams on his face and he laid out, yet he was cold. He was hungry. He was tired and he missed Izuku deeply.
Katsuki had not eaten, not slept and not rested since he’d been lost. Somehow, the thing he wanted most was not any sustenance for himself. His dying wish was that he could apologize to his mate. He wished that he could tell Izuku that he was sorry, and tell him how hard he tried to make it home!
But at least his love was safe and warm in their Den, surrounded by their friends and family. Katsuki had full faith that the Pod had found Izuku and took care of him.
Izuku would live on without him, a long and happy life! Katsuki could be content with that.
Just as he was ready to sink further down and give up completely, something hard pressed against his back and pushed him upwards. Bumping him gently closer to the sun and away from the abyss.
The pressure against his back lifted him up, up and up until he was above water! Air touched his skin and a burst of sea spray spouted next to his head, scaring Katsuki back to life.
His heart raced as he sat up upon the rough surface he was sitting upon, breathing oxygen for the first time in many moons and it helped reset his system. Like a direct deposit to his brain that woke him up from a bad dream.
Looking down, Katsuki saw that he was sitting on a humpback whale! His first reaction was panic and he scrambled off of its back and into the water. But the whale followed him with gentle eyes and Katsuki was flooded with a sense of calm.
“You saved me.” He digested the knowledge.
The humpback made a noise that sounded like a mix between clicking and whistling, which made the surface of the water vibrate above them.
“Thank you.” Katsuki bowed. He wasn’t sure if that was the right thing to do, but he wasn’t sure what else would be appropriate. This creature just saved his life!
The whale dipped his head in response and turned its massive body to the side with another vocal click.
“You want me to follow you?” Katsuki had no other ideas or direction to go and anywhere was better than here. “Sure.”
Maybe the whale would take him to his Pod and Katsuki could live with them? At least he would have company and wouldn't have to be alone anymore.
“I hope you have food wherever we’re going.” He latched onto the humpbacks right pectoral fin and held on tight.
With a sound of glee, the whale started to move and holy shit! Katsuki thought the shark was fast, but it had nothing on this whale! Katsuki held onto the fin with all his might and still he felt himself slipping.
“Woh! Slow down!” He yelled.
Thankfully, the humpback eventually did slow down and set a better cruising speed that was comfortable for the both of them. If Katsuki were at full strength, he’d probably be able to hold on easily. But he was definitely not at full capacity.
He relished the feeling of the water rushing in his hair and past his fins, it had been a while since he had the strength to swim at full speed. The feeling was refreshing and rejuvenating, making him feel alive again.
But also guilty, because wherever the whale was taking him, it was probably not back to Izuku. Katsuki wasn’t sure if he would ever be able to find his way back to the reef. He tilted his chin down at the thought of abandoning his Pod, his love.
It gouged a hole through his heart, but the ocean was so vast and the Reef was one small place. He would never stop looking as long as he was alive, but the light of his hope was almost nonexistent.
As his head was pointed down, his eyes caught the sight of sand. Sand?! He hadn’t seen the ocean floor since the attack! Whipping his head upwards, he saw seaweed, rocks and coral in the distance.
He started to hyperventilate with joy when the landmarks slowly became familiar. The whale was bringing him home!
Emotion bubbled over and shook his entire body, forcing a wet cry from his throat and tears from his eyes. Letting it all out, Katsuki sobbed upon the whale's fin as it carried him over more colorful coral.
“T-thank you-u. Thank you s-so much.” He could barely get the words out and the whale clicked happily in response.
Soon enough the water grew too shallow for it to go any further and it turned its body, a signal for Katsuki to continue on his own.
“I cannot thank you enough, my friend.” Katsuki pressed his body against the side of the whale, like a giant hug.
With one last hum, Katsuki pushed off and swam with all his might the final length towards the Reef.
Home. Izuku Home! Izuku! The words repeated on loop in his brain as he forced himself on the last stretch! Then he could see his love, eat and sleep! But he had to get there!
Up and over the familiar crest of the Reef’s ridge and it came into view, his heart soaring at the sight of caves and Mers! He practically sunk down into the grotto, allowing his weight to carry him.
He caught sight of Kirishima and he called out for help. “Kirishima!”
The Crab Mer stopped in his tracks and screamed when his eyes landed on Katsuki. “Katsuki?!”
His friend ran to him with his many legs and caught him from sinking into the sand.
“Oh fuck, you’re alive!”He cried and hugged him tightly enough not to hurt his injuries. “You look terrible!”
“Gee thanks.” Katsuki rolled his eyes, fuck it was good to be home.
“We were so worried about you, where were you?!”
“Didn’t Izuku tell you?”
“Oh shit, Izuku!” A look of realization sparked in Kirishima’s eyes, a spark that triggered panic in Katsuki. “There's no time to celebrate! We have to get you to Izuku, now!”
Kirishima was already on the move, expertly crawling around the corals and towards where they needed to go.
“What do you mean, what's wrong with him?” He demanded.
“He hasn’t woken up since you disappeared.” The crab Mer explained with haste. “Aizawa and Recovery Girl say he’s getting worse. He needs you!”
Izuku hadn’t woken up since the accident? Was his injury that bad? It was bleeding a lot, but it did not look life threatening. Something else was going on and it felt wrong.
“How long?” Katsuki dared to ask. “How long have I been gone?”
“About a week.”
“Fuck.”
The arrived at Inko’s house and Katsuki didn’t even bother announcing his presence, he barreled inside and looked for Izuku.
“Katsuki?!” The voice of his mother caught his attention first. “We thought you were dead!”
She pulled him into a hug, showing vulnerable emotions that were uncommon for her personality.
“What took you so long?” His father approached from the front, foamy tears floating from his eyes.
“Sorry.” He didn’t know what else to say.
He hadn’t even thought about the effect his actions would have on his parents. Of course they had every right to be angry with him, but according to Kirishima, no one knew what happened.
“Izuku.” He pressed.
“Of course.” Mitsuki let him go and led him to Izuku’s old bedroom.
Inside the familiar space, he saw Inko curled by the bedside, expectedly crying. But her tears turned to shock as she saw Katsuki enter.
Katsuki would have said something to her, but his attention was drawn to the bed where he saw Izuku and his heart broke.
This was not the reunion Katsuki thought they’d have, Izuku was not yelling at him, not crying. He was dying.
The mandarin fish pigment of his tail and fins had faded white, even his hair had turned white. He looked sickly and pale, unresponsive and deathly.
“Zuku…baby, come back to me.” Katsuki sunk down by the seabed and clutched his hand tightly. “I’m here, I came back to you. Don’t leave me now.”
“He’s been like this for days.” Inko sniffed.
“Why?”
“We weren’t entirely sure, since we didn't have the full story.” Recovery Girl entered the small space. “We assumed he must have gone through something traumatic that caused him to shut down. His injuries have healed, but his mind is giving up.”
Katsuki took one look at the dark circles under Izuku’s eyes and cursed under his breath. “Fuck you Izuku.”
Of course Izuku would do this.
“Don’t you go thinking I’m dead asshole, not after all the shit I went through to fuckin survive! You don’t get to give up and leave me behind!” Katsuki got right up in his face and yelled.
But there was no reaction. Katsuki let his head drop onto Izuku’s chest, he was exhausted.
“Please, let us tend to you.” Recovery Girl tried to remove him from Izuku, but Katsuki lashed out.
“No! Not until he wakes up!”
“Katsuki, you need medical attention!”
“I said no! Now leave us alone!” He demanded, using the last bit of his strength to pretend like he had more.
Reluctantly, they left the room one by one and drew the seaweed curtain closed. Giving them some privacy. Once alone, Katsuki couldn't wait any longer and he climbed into bed with his mate.
He needed to feel him close and smell his scent, though it wasn’t as familiar and comforting as he’d like. Izuku’s body was cold to the touch and his scent was dull and slightly sour.
“Come on Zuku, you are so strong. Stay with me. Please.” He gripped his lover's head between his hands and forced their foreheads together.
Foam tears sprouted from his eyes and floated round the room as he begged Izuku to wake up. After everything they had gone through, they deserved to live, to be with each other! Katsuki made it home! Izuku deserved to know that! That he didn’t die by the shark and he came back to him!
“Please.” He placed a kiss on his forehead.
“Please.” Another on his cheek.
“Please.” On his lips.
Izuku’s gills flared and suddenly took a deep breath, body shivering and reacting to the kiss.
“Izuku!” Katsuki called his name and adjusted him to a more comfortable position when the Mer started coughing.
“...K-Kacc-han…?” His voice sounded croaked, like he hadn’t used it in a long time.
“Yes baby, it’s me. I’m here.” Katsuki couldn't stop the smile from his face, joy filling his entire being.
“Are we dead?”
“No.” He laughed. “We are both alive and home.”
Katsuki kissed him more and more, planting them everywhere he could and Izuku couldn’t stop him since he was so groggy.
“Hey, cut it out.” It obviously hurt to laugh, so he stopped. “I’m still mad at you, don’t ever scare me like that again.”
“I won’t. I promise I will never leave you ever again!” Katsuki had a lot to tell him.