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The lighthouse stood tall against the roiling grey sky, its lens ever sweeping, vigilant and alone. Katsuki Bakugou had kept it that way for the past ten years. Alone, that is. He didn’t mind the isolation. Not anymore. The sea didn’t ask questions, didn’t judge, didn’t expect pleasantries. It was brutal, honest, endless. Just like him.
His house sat stubbornly at the edge of the cliffs, the light tower its ever-watching eye. A single winding path led down to the beach below, narrow and treacherous. No one ever visited. No one ever came.
Until today.
Katsuki spotted it, or rather, him , from the kitchen window just past dawn, when the sky was still the color of cold ash. A shape, unmoving, lying where the tide had left it. At first, Katsuki assumed it was a seal, maybe a dolphin. He’d seen both before, stranded and bloated with salt. But when he got closer, the breath froze in his throat.
It wasn’t a something. It was a someone .
Pale skin with a strange, cold shimmer to it. Hair split starkly down the middle, one side snow white, the other a deep, rich red. There was a scar that twisted across the left side of his face, angry and raised, and his limbs… too long, too lean, were trembling against the sand. Katsuki hesitated, kneeling beside him.
Not breathing.
Shit.
He pressed his hand against the man’s chest, skin cold like marble, and then, mercifully, a shudder. A cough. A gasp. Saltwater spilled from his lips and he jerked, like a puppet cut from strings.
Katsuki hauled him up without thinking.
He didn’t think. He didn’t question. Not until after he’d dragged the stranger through the front door, stripped off the soaked, barely-there fabric clinging to him like seaweed, and dumped him into his bed beneath the thickest quilt he owned. Only then, standing in the doorway, staring at the unmoving figure in his sheets, did Katsuki realize:
What the fuck was he doing?
The man woke with the sound of gulls screeching outside. Katsuki had been sitting nearby, elbow on the windowsill, watching.
He stirred slowly, lids fluttering open to reveal strange eyes, one grey, one turquoise. Cloudy and waterlogged, but alive. Very alive.
The stranger looked around, wide-eyed. He sat up, the blanket falling to his lap, exposing a long, pale torso that shimmered faintly like something not-quite human. Katsuki looked away, swore under his breath, and shoved the man’s damp clothes at him.
The man blinked at them like he didn’t know what they were.
“I don’t know who the hell you are,” Katsuki started, tone gruff, “but you nearly drowned out there.”
The man turned toward him sharply, eyes lighting up like he heard something familiar, but then… he started chirping . No, not words, just a series of clicks and warbles and soft whistles, like birdsong filtered through seawater. Like dolphins. Whales. Things that sang instead of spoke.
Katsuki stared.
“What... the fuck ?”
Another chirp. The man tilted his head.
Katsuki tried again. “Do you understand me?”
The man just blinked, then gave a low trill that rose like a question.
“Shit.”
He was definitely not human. Or if he was, he wasn’t from any part of humanity Katsuki knew. No one spoke like that. No one moved like that. His skin, his hair, his eyes-
The man made a noise, soft and insistent, like asking for help. He tried to swing his legs off the bed.
Katsuki stood quickly. “Oi, don’t-!”
Too late. The man stood, and then immediately collapsed, his knees buckling beneath him like kelp in a strong current. He hit the wooden floor with a sharp thud, long arms sprawled out beneath him.
Katsuki cursed, rushing over. “Dumbass! What did you think was gonna happen?!”
The man made a high-pitched whine, somewhere between pain and confusion. Katsuki knelt down beside him, grabbing his arms to lift him back into the bed. The stranger's skin was still far too cold, his muscles trembling like a newborn foal's.
The man stared at him, wide-eyed, as if studying the shape of Katsuki's mouth, the weight of his hands. Then, quietly, he reached up and touched Katsuki’s cheek with two fingers, light as a tide pulling back.
A question. A name, maybe. A plea.
Katsuki stared right back. “I don’t know what the hell you are,” he muttered, “but the sea spat you out. That’s gotta mean something.”
The man chirped again. Lower, softer. Almost... grateful.
And Katsuki, against every bitter instinct he’d cultivated in his ten years of solitude, sighed and muttered, “Guess I’m stuck with you now, huh?”
The man blinked slowly, tilted his head, and for the briefest moment, he smiled. Not fully. Not like a human. But enough to make something strange and warm curl in Katsuki’s gut.
He had always watched from the shallows. Always lingered where the reef fell off into dark waters, where the waves whispered secrets and the rocks hid him from sight. Always watched the man with the golden hair and the sun in his eyes, as he walked the same cliff path every day with sure steps and a scowl that never quite reached his mouth.
Ten years.
Ten years, and Shouto knew the shape of the lighthouse like he knew the push of the current. Knew when the man chopped firewood, when he fished, when he stood staring out into the sea as if daring it to answer something it never had. He watched him, heart full of something curious and warm, fins brushing against kelp like a nervous pulse.
This man, this human , was different.
Shouto had always been interested in humans, but none quite like him. Blond. Strong. With legs. Legs that let him run and dance and move across the earth like he belonged to it. Legs that could take him far, yet he stayed , here, in this lonely corner of the world.
Shouto didn’t know what it was, exactly. Just that he wanted to understand. He wanted to be understood. He wanted, more than anything, to meet him.
But how could he? A tail of scales and seafoam would never climb cliffs. Would never walk beside a man like that.
So, he made a deal.
A pair of legs for his tail. The sea witch asked nothing more. No voice. No memory. No true name. Just the tail, the part of him the land could never accept.
It seemed fair enough.
Until he washed up half-dead on the beach.
The air hurt.
That was the first thing he noticed. Not in the way the sea hurt when it was angry. This was worse. This was emptiness where water should be.. His new lungs, raw and untested, clawed desperately for breath.
The last thing he remembered was the tide sucking him under. His legs, legs , not fins, had no strength. The water didn’t hold him anymore. It rejected him. He couldn’t swim. He couldn’t breathe. He couldn’t call for help.
And then… him .
The man.
His arms, strong and grounding. The faint scent of smoke and salt clinging to him. The warmth of the house that wrapped around Shouto like something sacred. The softness of cloth, the way the wind didn’t bite inside this place. He was placed in a bed. Covered. Saved.
The man didn’t know who he was.
Didn’t know Shouto had watched him from tidepools and sea caves. Didn’t know how many nights Shouto had sung to the stars with the hope the man might hear. Didn’t know that this was all because of him .
Shouto blinked awake slowly, each moment brimming with aching confusion. His legs still trembled. His chest burned. But the man was there.
Shouto sat up, tried to speak, and a whistle came out. Instinctive. A sound of the sea. He tried again. Clicks. Warbles. A melody made for water, not air.
The man stared, baffled.
Shouto’s stomach twisted. He didn’t think to ask the sea witch for a language. He hadn’t even thought about how humans spoke, only that they did. He hadn’t planned. He was too enchanted. Too reckless.
Ah... this isn’t good, Shouto murmured in his own tongue, the words falling from his mouth like broken waves.
The man said something. Sharp. Confused. Loud.
Shouto flinched.
He looked around the room. The textures. The weight of gravity. The scratch of blankets against skin. He was human now, yes, but he didn’t know how to be one. The simplest things were unfamiliar. Heavy. Wrong .
And yet, the man... he looked at him with narrowed eyes, not cruel, but questioning. He reached out once to stop Shouto from trying to stand again, his voice low but firm. There was something careful in his touch, as if he wasn’t used to touching people at all.
Shouto’s chest tightened. He wanted to say thank you. He wanted to say I’ve seen you before . He wanted to say I chose this because of you.
But all that came out was another quiet trill. His tongue didn’t know the words.
So, he nodded.
The man blinked.
Then, to Shouto’s surprise, he grunted, just one syllable, and pointed at himself. “Katsuki.”
Shouto tilted his head.
The man, Katsuki, pointed again. “Katsuki.”
Shouto’s lips parted.
A name. He’d told him a name.
That meant... that meant he could learn. Shouto could try .
He swallowed, slowly pointed at his own chest.
“...Shouto.”
Katsuki looked at him. Then gave the faintest of nods. No smile. But no rejection either.
It was a start.
Shouto collapsed back into the sheets, tired and dry and barely understanding what he’d done to himself. But Katsuki was there. And Shouto, once a creature of salt and song, was here. On land. In a body he did not yet know.
And even if it took weeks, months, years...
He would learn to walk.
He would learn to speak.
He would learn to stay .
Because Katsuki was real.
And he was worth the price.
He didn’t know what he was doing.
Katsuki Bakugou had lived in solitude for a decade. The rhythm of his life was steady and sure: keep the light burning, fix what breaks, cook, eat, sleep, survive. There was no need for more. No want for more.
Then he showed up.
Washed ashore like driftwood, half-drowned and barely breathing, with skin like cold porcelain and hair like a wound split in two, half blood-red, half ghost-white. And those eyes ... two different colors, both too clear, like glass polished by the sea. They didn't belong to any human Katsuki had ever seen.
That was his first clue.
The second was the way the guy sounded . Not like a foreigner. Not like someone who spoke another language.
Like someone who didn't speak at all.
He chirped. Whistled. Trilled like a goddamn dolphin. And he didn’t understand Katsuki, no matter how slowly or loudly he spoke.
Still. Still, Katsuki didn’t throw him back to the waves.
He gave him clothes. Let him eat, gods , the way he ate, like he’d never tasted food before, and pointed to things around the house, saying their names. “Cup. Spoon. Table. Fire.” The guy, Shouto , would listen, brows furrowed, head tilted like a bird. And then, slowly, he’d mimic them.
“...Cu-puh.”
“Ta-buh.”
“Fi-re.”
Each syllable an effort. Each small success something that made Katsuki feel... something.
He didn’t know what, exactly. Pride? Satisfaction?
Annoyance that he felt anything?
Sometimes, at night, when Shouto had fallen asleep curled up on the couch with a blanket wrapped too tightly around him (he always slept like he was trying to hide), Katsuki would sit at the edge of the porch, cigarette forgotten between his fingers, and think.
Why the hell am I doing this?
He didn’t know Shouto. He didn’t owe Shouto. And gods, the guy was so clearly not normal. Not human. The way he moved… too fluid, too silent. The way he stared at water like it meant something. The way he flinched when the stove hissed and glared at seagulls like he was trying to speak back.
It wasn’t right .
And yet... Katsuki couldn’t turn him away.
Maybe it was the way Shouto looked when he said a word right, eyes lighting up, a small, barely-there smile tugging at his mouth like he’d just uncovered some secret treasure. Maybe it was how determined he was, how even when he fumbled and stumbled and forgot, he tried again.
Or maybe, though Katsuki would never admit it aloud, it was because Shouto was kind of pretty.
Ridiculously pretty.
His hair stayed a little damp all the time. He didn’t seem to know what to do with shoes. And he had this habit of leaning way too close when Katsuki was talking, like he could hear better if he was breathing his damn air. Katsuki told him to back off more than once.
He never listened.
And maybe Katsuki didn’t really want him to.
One morning, he was teaching Shouto how to cook eggs. A simple thing. Just a skillet, some oil, some cracked shells.
“Not like that,” Katsuki snapped when Shouto nearly dropped the yolk in the sink. “You gotta be gentle . Crack it here.” He demonstrated again. “Edge of the counter. Soft .”
Shouto nodded, serious as ever. Lips pressed in concentration. He tried again. Slow. Careful.
Crack.
Perfect.
“...Egg,” Shouto said, a little smug.
Katsuki blinked. “Yeah,” he said after a beat. “That’s... that’s right.”
Shouto turned to look at him, glowing like he’d won a battle. The sunlight caught the side of his face, highlighting the scar Katsuki never asked about, the faint shimmer still lingering on his skin like the sea hadn’t let go.
For a moment, Katsuki forgot to breathe.
“Good job,” he muttered gruffly, turning away and pretending to wash something that didn’t need washing.
Behind him, he heard a soft chirp. And then:
“Ka...tsu...ki.”
His name.
Not perfectly said. Not sharp like he said it himself. But it was there, shaped by lips that had never spoken any human tongue before.
Katsuki gripped the edge of the sink.
Goddammit.
He didn’t know what Shouto was. Didn’t know why he’d shown up. Didn’t know why he tried so hard to stay.
But maybe, just maybe , he was worth keeping around.
Not that Katsuki would say that out loud. Hell no.
He just turned, tossed a dishtowel at Shouto’s face, and barked, “Next time you burn the eggs, I’m feedin’ you to the gulls.”
Shouto caught the towel, smiling quietly.
And Katsuki, against his better judgment, smiled too. Just a little.
Just enough.
Shouto was spellbound.
Everything about Katsuki, his strength, his voice, the way his hands moved when he spoke, fascinated him to no end. There was power in him, yes, but not the cruel kind Shouto had once feared in the deep trenches of the sea. It was sharp, warm, crackling like fire caught in human skin. And Shouto, now made of legs and lungs and things that ached, was hopelessly drawn to it.
Drawn to him .
Katsuki had become his lighthouse in every sense. A fixed point. A guide. A flame he couldn’t swim away from, even if he wanted to.
So when Katsuki told him to do something, even if Shouto didn’t entirely understand the words, he tried. Earnestly. Obediently.
He folded laundry the way Katsuki showed him, even though it took three tries and a few growls of frustration. He swept the floor, carefully copying Katsuki’s motions. He practiced words Katsuki pointed at, “bowl,” “door,” “sky,” “mine” , until they no longer stuck to the roof of his mouth.
And slowly, his world began to grow.
Sentences came next. Small, broken ones.
“This is… fire.”
“Katsuki is… mad.”
“I like… tea.”
Sometimes Shouto said things just to see Katsuki’s reaction. Like when he said “Katsuki is… pretty,” and the man turned red as the sunset and snapped, “Don’t say shit you don’t understand, dumbass,” before promptly leaving the room.
Shouto smiled for hours after.
One day, Katsuki left for the mainland. He’d done it before. Short trips, always returning before dark. But this time, he was gone for hours. The light in the tower stayed on, but the house felt cold. Empty. Wrong.
Shouto paced. Sat. Stared out the window with his chin resting on the table, his fingers fiddling with the edge of his shirt.
When Katsuki finally returned, windblown and scowling, Shouto nearly flung the door open in his face.
Katsuki blinked. “...You okay?”
Shouto didn’t answer. He just reached out and grabbed the hem of Katsuki’s coat with both hands. Katsuki didn’t pull away.
Instead, he huffed. “I got you stuff.”
Stuff, as it turned out, meant treasures .
Trinkets. A shell-shaped soap dish. A scarf in soft, sea-glass green. A box of colored pencils that Shouto immediately sniffed. And books. So many books.
Some were thin and bright, with big pictures. Others thick, heavy, with lines of squiggles and dots Shouto couldn’t begin to understand.
Katsuki dropped them on the table with a grunt and said, “We’re gonna teach you to read.”
We .
As if they were a team.
Shouto touched the cover of the nearest book, reverently. He turned the pages with care. The symbols were odd, little lines that seemed to dance and shift if he looked too long. But Katsuki sat beside him, patient despite the usual scowl, pointing to letters, mouthing their sounds.
“A. Like in apple .”
“B. Like in boat .”
“C. Like come here and sit your ass down , idiot.”
Shouto laughed. It was still new to him, laughter, but it felt right here.
He practiced each sound, each word, stumbling at first. But Katsuki didn’t yell. Well, not really. He corrected, repeated, tapped the page with his finger. Showed him how to write his name.
Shouto . In careful strokes. S. H. O. U. T. O.
It was magic.
Magic he could touch.
Magic he could do .
And in return… Shouto gave everything he had. His attention. His effort. His silent devotion. He cooked clumsily but did it anyway. He watched Katsuki fix things around the house, memorizing how his hands worked. He followed him into the garden, asking the names of plants, the colors, the feel of soil between fingers.
He learned to walk better. To stand without swaying like a tide-pulled boat. Katsuki showed him how to use his legs, his legs, with balance, with strength. It was hard. Everything was hard.
But Katsuki was always there.
Helping. Catching. Cursing and sighing but staying.
And every day, Shouto wondered: How do I thank him?
How do you repay a man who gives you language, footing, warmth, and a name worth hearing?
How do you give something back when your old world had no words for kindness, no rituals for gratitude?
Some nights, when Katsuki had gone quiet and the house had gone soft, Shouto would sit near the lighthouse window, legs drawn to his chest, and whisper the new words he’d learned to the sea.
“Thank you. Katsuki. Fire. Home.”
And he hoped that somehow, in this language of light and learning, Katsuki could feel how much he meant.
Even if Shouto didn’t know how to say that yet.
Katsuki never liked company.
That had been the whole damn point.
Ten years alone on the edge of the sea, the wind and waves the only things that ever dared to raise their voice at him. And he liked it that way. He didn’t need people. Didn’t want them. Didn’t trust himself with attachments. They asked for things. Needed things.
And Katsuki… Katsuki was better when no one needed anything from him.
But then he washed up.
Everything about him had screamed not huma n.
And yet Katsuki had taken him in.
He still doesn’t know why. Maybe because the idiot looked too helpless, sprawled on the shore like a broken piece of driftwood. Maybe because he twitched when Katsuki reached for him, but didn’t run. Maybe… maybe because those eyes looked at him like he mattered.
Whatever the reason, Shouto had stayed.
And now, Katsuki realizes, he's gotten used to i*.
Used to hearing footsteps other than his own. Used to that quiet voice slowly stringing together his language like seashells on twine. Used to Shouto’s presence curled on the couch, fingers flipping through picture books with reverence.
Used to him looking at Katsuki like the damn sun rose out of his boots.
He cussed at him out of habit, sure. “ Idiot.” “Moron.” “Don’t put metal in the microwave, dumbass.” Nut Shouto never seemed to mind. Hell, sometimes he even smiled when Katsuki did it. Smiled like he thought it meant something else.
Compliments, maybe.
God, he was so weird.
And Katsuki…
Well.
He didn’t hate it.
Didn’t hate him .
And that was the problem.
Katsuki lays in bed, arms folded behind his head, the glow of the lighthouse circling gently through the window. Shouto’s curled on the couch in the next room, swaddled in three blankets like a caterpillar that hadn’t quite figured out the whole metamorphosis thing.
Katsuki should be asleep.
But his brain’s chewing through questions like a dog with a bone.
Can Shouto leave?
Should he?
Would he want to, if he could?
And what happens if he does?
What happens if Katsuki wakes up one day and there’s nothing left but the sound of gulls again?
He grits his teeth. Stupid thoughts. Attachment was stupid. Caring was stupid.
But then-
A sound cuts through the night. Sharp. Piercing.
Whistles. Trills. Rapid and desperate, like a warning call from a creature that didn’t belong to the surface world.
Katsuki sits up instantly.
“Shouto,” he mutters, already on his feet.
He storms into the living room, heartbeat racing. Shouto’s thrashing under the blanket, his voice rising in that strange, old tongue. His real tongue. The one Katsuki still didn’t understand.
A nightmare.
“Oi,” he crouches beside the couch, gripping his shoulder, shaking him gently. “Shouto. Wake up.”
The whistles stop abruptly.
Shouto’s eyes snap open, wild and glistening.
“Katsuki,” he breathes. His name , spoken clear and trembling.
And then, before Katsuki can say anything, Shouto launches into his arms.
Katsuki freezes.
The weight of him. The heat. His arms wound tight around Katsuki’s neck, his body trembling like reeds in a storm. There’s a wet patch growing on Katsuki’s shirt where Shouto’s face is buried.
He’s crying.
Katsuki swallows thickly.
“You’re fine,” he mutters, unsure if he’s trying to convince Shouto or himself. “It’s just a dream.”
Shouto doesn’t respond. Just squeezes tighter.
Katsuki lets out a long breath and pats him on the back awkwardly.
“Alright. Enough. Let go now. I wanna go back to bed.”
But Shouto doesn’t move.
Just a soft, “No.”
Spoken small. Determined.
Katsuki sighs, and the sound comes out more fond than he wants it to.
“Shit. You’re lucky I’m soft.”
With a grunt, he hooks one arm under Shouto’s legs, the other around his back, and lifts him easily. Shouto doesn’t protest. Doesn’t even blink. Just nestles closer like Katsuki’s chest is the only safe harbor in the world.
He carries him back to bed. The blankets are still warm.
Shouto clings even as Katsuki tries to roll over. He ends up curled against his side, fingers gripping Katsuki’s shirt like he’s afraid he’ll vanish.
“Just one night,” Katsuki mutters under his breath.
But he doesn’t pull away.
Not once.
Not even when Shouto sighs softly in his sleep and presses his forehead to Katsuki’s shoulder like a prayer.
And somewhere between the heartbeat in his chest and the soft rhythm of Shouto’s breathing, Katsuki wonders, maybe he doesn’t mind being needed.
Not by him.
The dream didn’t feel like a dream at all.
It started in the deep. Not the soft sea near the beach where waves played gently against the shore, but the ancient dark, where light never touched. Shouto was drifting there, weightless, silent, breathless in a way that felt familiar and wrong all at once.
Then came the voice. Cold. Crushing.
“You’ve stayed too long, son.”
It echoed inside him, not around him, pressing against bone and heart. He knew it instantly. It was the voice he’d been trying to forget, even beneath the lull of the human world.
His father.
The Sea King.
The old ruler, the one whose wrath shaped tsunamis and whose pride turned coral reefs into graveyards.
“Return. Or he dies.”
Shouto’s heart snapped like a reef under pressure.
“No,” he gasped, but there was no sound underwater. Only the choking silence and the growing pressure. “Please don’t-”
“You’ve taken something from me.”
Shouto shook his head violently. “I’m not yours anymore!”
But then Katsuki appeared, in the water too, sinking fast, his hair drifting like kelp, eyes wide with a panic he didn’t know how to swim with. He reached for Shouto, mouth moving soundlessly.
“You love him?” the voice asked, quieter now, cruel.
“Yes,” Shouto whispered, eyes stinging with tears even underwater. “Yes. Please. Don’t hurt him.”
The shadows surged toward Katsuki, sharp, monstrous, hateful. Shouto screamed-
And bolted upright.
The air was too dry. The room too still. His chest heaved with the effort of breathing.
“Shouto.” Katsuki’s voice. Grounded. Here. Real.
Then arms. Warm. Wrapping around him from behind. Shouto turned blindly and grabbed at him like a lifeline, burying his face in Katsuki’s chest and letting the sobs come.
He didn’t remember what he said. Maybe he didn’t say anything. But Katsuki didn’t push him away. He just held him. One big hand stroking his back slowly, the other around his waist like a tether.
That night, Katsuki let him stay.
And the next night.
And the next.
Sometimes Katsuki would sigh and grumble, lifting Shouto like he was some lazy cat curled up in the wrong spot and mutter something like, “Damn clingy idiot,” but his arms never loosened.
At some point, Katsuki stopped pretending he didn’t like it.
Shouto never mentioned the dream again. But it lived in him now, like the memory of drowning. A slow ache in his ribs. A constant reminder that the time he had here, with Katsuki, might be borrowed.
So he stayed close.
Close enough to memorize the rhythm of Katsuki’s breath, the rise and fall of his chest. He counted the freckles on his shoulders. Learned the names of things in whispers in the dark, even if Katsuki sometimes groaned at his questions.
“It’s a bookshelf.”
“No, Shouto, I don’t know who invented pants.”
He loved him. Quietly. Fiercely. With every clumsy human word he learned, with every touch he dared give.
But then… that night.
Katsuki was behind him, arms snug around his middle, breath hot against the back of his neck. Shouto liked it, being held like that. Safe. Tethered.
But tonight… something was different.
There was a pressure. Something poking… right at his lower back.
Katsuki made a strange sound, half gasp, half grunt, and his grip tightened a little.
Was he sick?
Shouto blinked, confused.
He reached down carefully, feeling Katsuki’s arm, then lower, where the pressure was.
There.
A strange tent shape in his pants. Right between his legs.
Curious, Shouto poked it.
Katsuki jolted. Groaned.
Shouto paused. That wasn’t pain. Maybe it was swelling? Inflammation? Humans were so fragile.
He tried squeezing it gently, to see if it would go down.
It did not go down.
Instead, Katsuki bolted upright with a sound like someone stepped on a live wire. His face was beet red.
“What the hell, Shouto?!”
Shouto flinched, confused and startled.
“... What?”
“Don’t- don’t touch that!” Katsuki was sputtering now, his hands flailing, trying to hold a blanket over his lap and point to the door at the same time. “Out! Just- Go!”
Shouto stood up slowly, stunned. “I hurt you?”
“Go, dammit!”
Shouto nodded dumbly and shuffled toward the door, still frowning. He didn’t *think* he did anything wrong, but Katsuki was clearly upset.
Humans were weird.
Still, as he sat on the couch in the dark, legs curled to his chest, he made a mental note.
He’d ask Katsuki about it in the morning.
Maybe after breakfast. When Katsuki was less red in the face.
He wanted to understand. Wanted to learn everything about him. Even the strange parts Katsuki tried to hide.
Because Shouto loved him.
And he’d learn the whole language of Katsuki if it meant he could stay.
It was a dream. He knew it was a dream, even as it sank its teeth into him like something real.
Shouto was beneath him. Naked, flushed all over, that pale skin turned pink and red in places Katsuki shouldn’t be looking, but couldn’t stop staring at. His mismatched hair fanned over the pillow, those wide, ocean-glass eyes locked on Katsuki’s like they always did. Bright, adoring, trusting.
“Katsuki… please-”
That voice. Soft, hushed, needy. Like a prayer.
His legs were spread, drawn up willingly, like he’d done this before. Like he wanted it.
Wanted him .
Katsuki was above him, frozen in the ache of that want, of how perfect he looked. Flushed and hard, cock twitching softly against his stomach, arms reaching for Katsuki like he already belonged there.
And Katsuki… fuck. He didn’t deserve to be in that dream. Didn’t deserve to be seen the way Shouto was looking at him.
But still-
Still, he leaned in-
Until something squeezed him.
His eyes flew open.
Katsuki jerked upright with a strangled noise, half-choked between a gasp and a curse. Sweat clung to his back. His cock, fuck , was hard, very hard, and someone was-
Shouto.
Katsuki yelled, telling him to get out.
Shouto flinched like Katsuki had slapped him.
He looked confused. Then hurt. Truly hurt.
He sat back slowly, then slipped off the bed, barefoot, still in the oversized shirt Katsuki had given him. He didn’t say anything as he left, didn’t even glance back.
The door clicked shut.
Katsuki stared up at the ceiling, heart thundering.
Fuck .
The morning came cold and thick with silence.
Shouto was quieter than usual. He moved around the kitchen like a ghost, eyes cast down, not asking about names or colors or the little things like he always did.
Katsuki sat at the table, arms crossed, coffee cooling in his mug. He watched Shouto hesitate by the stove, like he wasn’t sure if he was allowed to cook eggs today.
“Don’t,” Katsuki muttered, eyes flicking away. “I’ll do it.”
Shouto nodded. Sat at the edge of the table. Silence again.
He fidgeted. Opened his mouth. Closed it.
Then, finally, “Are… mad?”
Katsuki’s jaw tightened. “No.”
“You yell.”
Katsuki rubbed a hand over his face. “I just-” He couldn’t finish that sentence.
Shouto waited. Always so patient. It made it worse.
“You… not want me…?” Shouto asked softly.
Something sharp twisted in Katsuki’s gut.
“I didn’t say that.”
“But you-” Shouto’s words stumbled apart like tidefoam. “You… scared. Of me?”
“No!” Katsuki slammed his mug down without thinking. “No. That’s not-” He exhaled hard. “I’m just… figuring shit out, okay?”
Shouto didn’t understand all of that. Katsuki could tell. But he nodded anyway.
Then he didn’t come to bed that night.
Katsuki waited, like an idiot. Pretended to read. Pretended to not notice how quiet the hallway was. How cold the blankets were.
At midnight, he got up.
The couch was too small for Shouto, curled up like a damn sea cat in a shirt that had slipped halfway down his shoulder. His back was to the room. He was pretending to be asleep.
Katsuki sighed. “You’re an idiot.”
No response.
Katsuki stepped forward. Reached down.
Shouto flinched.
Katsuki hesitated. Then picked him up.
Shouto didn’t fight it. Just leaned into his chest like always, silent and warm, his fingers curling into the fabric of Katsuki’s hoodie.
Back in bed, Katsuki laid him down gently, then crawled in beside him. Shouto looked up at him, eyes heavy, unsure.
“I’m not mad,” Katsuki muttered. “Just stupid.”
“Not stupid,” Shouto whispered.
Katsuki chuckled under his breath. “You don’t even know what that means.”
Shouto leaned forward, tucking himself into Katsuki’s chest again.
Katsuki held him.
He didn’t know how to explain the dream, or the heat that still lingered in his body, or how dangerously close he was to falling for this strange, soft-eyed, brave-as-hell man who’d come from the sea and somehow made him feel like staying.
So he didn’t say anything.
He just held Shouto close and hoped the silence said enough.
It was a dream. He knew it was a dream, even as it wrapped around him like warmth from beneath the blankets.
Katsuki was holding him, arms around his waist, steady, safe. His body radiated heat even in sleep, even in dreams. But that wasn’t what made Shouto’s chest ache.
It was the kiss.
It started so softly. Katsuki leaned in, lips brushing his like a question. Shouto knew what a kiss was. He had seen it before, learned it was a gesture of intimacy. It was a promise. A vow. A wordless way to say, I want you close. I want you to know me.
And Katsuki was so gentle .
His mouth was warm. His hands cupped Shouto’s cheeks like he was something precious, something breakable. But wanted. Needed.
Shouto kissed back, in the dream. Not because he’d learned to, but because it felt right. Because this was Katsuki. And Katsuki was his.
When their lips parted, Katsuki looked at him like he’d never wanted anything more.
And then, like a tide rolling away, the dream faded.
Shouto’s eyes opened.
The room was dark. Cool. Quiet.
But the warmth was still there.
Katsuki’s arms were still around him. His face close. Lips parted. A quiet breath between them.
Shouto could feel Katsuki’s chest rise and fall, slow and steady. Could feel the faint thump of his heart.
He stared for a long time.
Katsuki.
He loved him.
He did.
That was the word for it. That warm ache that made his throat tight. That strange pull toward Katsuki’s voice, his hands, even his anger. He wanted to be near him always. Wanted to understand him. Wanted him .
He should tell him.
Not with words, he still didn’t have enough. Still didn’t know how to say all the strange things in his chest.
But maybe, maybe Katsuki would understand this.
He reached out and shook him gently. “Katsuki,” he whispered.
Katsuki grunted in his sleep, eyes fluttering open. “What the- Shouto?”
Before Katsuki could pull away, before he could snap or scowl, Shouto leaned down and kissed him.
Soft. Nervous. Honest.
Katsuki’s eyes widened.
His breath hitched.
Then-
He kissed back.
Fiercely.
Hands grasped at Shouto’s hips, pulling him closer, flipping them easily so Shouto was beneath him. Shouto gasped into his mouth, startled, but Katsuki didn’t stop. His lips moved against Shouto’s with purpose, with hunger. One of his hands slid behind Shouto’s head, cradling him.
Then, his tongue.
Katsuki licked into his mouth, slow but firm, and Shouto’s entire body went still. It was strange. Foreign. Merpeople didn’t do that . But it made his skin shiver, made his breath catch.
It was good .
Katsuki groaned low in his throat. Shouto moaned softly, surprised by the sound that left him.
He felt it then. Katsuki, pressed close, something hot and hard between them. Shouto’s own body responded, warmth pooling low, needy.
He didn’t know what was happening entirely, but he wanted it.
Katsuki was kissing down his neck now, whispering something against his skin. Shouto couldn’t understand it, but the sound made his stomach twist and flutter.
He whispered back, “Katsuki…”
Everything was heat and closeness and something new blossoming between them.
It wasn’t like the dream.
It was better.
Because Katsuki was real. Right here. Holding him like he mattered.
And Shouto had never felt more certain of anything in his life.
Katsuki didn’t know where the line had gone.
All he knew was that Shouto was beneath him, flushed, breathless, pliant. His mouth was red from kissing, his pupils wide and dark, his voice catching on soft, shuddering gasps every time Katsuki so much as touched him.
And fuck, Katsuki wanted .
He kissed him again. He couldn’t stop. Pressed their mouths together over and over, as if it might help burn the want out of his chest. But it only made it worse.
Shouto’s hands clutched at him, uncertain but eager. Every time Katsuki pulled back to breathe, Shouto chased his lips like he couldn’t bear to be without them. And Katsuki… Katsuki was unraveling.
One hand slid up Shouto’s shirt. His shirt, the one Shouto had borrowed that hung off his frame like it was made for someone else. He peeled it away slowly, almost reverently, baring pale skin inch by inch, marveling at the way Shouto shivered beneath his touch.
He leaned down, kissed along Shouto’s chest, heard the hitch in his breath. Bit gently at his ribs, his stomach. Shouto gasped.
“Okay?” Katsuki muttered into his skin, voice rough.
Shouto nodded, breathless. “Yes. Yes. Please, Katsuki…”
That voice… It lit Katsuki up from the inside.
He tugged the last of the clothes from Shouto’s body, tossed them somewhere he didn’t care to remember. All that was left was skin, soft and warm and pink from touch. Shouto’s legs trembled as Katsuki moved between them, as his hands wandered lower.
Katsuki kissed his thighs, nipped the inside gently, earning another gasp. Shouto’s cock was flushed, hard, resting against his stomach. Katsuki stared for a moment, longer than he should have, and licked his lips.
He could feel himself pulsing with need.
“Shit,” he whispered, grounding himself with one hand on Shouto’s hip.
Then- he reached into the drawer.
Shouto looked up, confused at first. Then wide-eyed. But he didn’t pull away. He nodded.
So Katsuki slicked his fingers, slow and careful.
“Relax,” he said, voice softer now, steadier. “You’ll be okay.”
The first touch made Shouto arch.
The second made him moan .
He was panting in no time, one hand fisted in the sheets, the other grabbing at Katsuki’s wrist like he didn’t know whether to push or pull.
“Doing so good,” Katsuki muttered, pressing a kiss to his knee. “So fuckin’ good.”
Shouto gasped again, his body twitching, hips lifting like he needed more . Katsuki gave it to him. Gave him everything he could.
Until Shouto was speaking in that soft, strange language again, words Katsuki couldn’t understand, but didn’t need to.
Because the way he held him, wrapped legs and arms around him, the way he whispered “Katsuki… more… ” that said it all.
And Katsuki… He he leaned forward, kissed him deep, slow, grounding. And when he moved, it was with aching care.
Shouto cried out softly, clutching at him, shaking. Katsuki whispered things he’d never said before. You’re okay, I got you, you feel so good, and hoped Shouto heard them, even if he didn’t understand.
Because Katsuki couldn’t hide it anymore.
He needed Shouto.
All of him.
And Shouto… he gave himself willingly.
Every sound, every shiver, every wordless cry beneath Katsuki’s hands, it was an answer.
Yes.
Yes, this was real.
Yes, this was theirs.
There were many words for what Katsuki did to him.
Sex. Fucking.
Crude, sharp-edged sounds that still felt strange in Shouto’s mouth, but Katsuki used them sometimes. Whispered them when Shouto straddled him, when he gasped and moaned and held on tight. When Katsuki was inside him, slow or rough, always good, always his .
Shouto just called it this .
This closeness. This warmth. This feeling that made his body hum and his heart hurt in the best way.
Katsuki liked it. Shouto liked it. That was enough.
They didn’t do it every night. Sometimes, they just curled together under the blankets, skin touching skin, Katsuki’s arms around him like an anchor. Shouto loved that most of all. It made him feel safe. Human. Loved.
He kept learning. Words, food, things like socks and movies and sarcasm.
He washed dishes, cleaned the floor, folded laundry wrong. Katsuki corrected him, gruff, but never cruel. Shouto listened, watched, tried again. He liked doing things right. Liked when Katsuki gave him that tiny, reluctant smile.
It was… nice. Their little world. Quiet. Warm. Something Shouto didn’t think he could ever have.
Until the day he saw them.
Just outside the window.
Still. Watching.
Their eyes like deep-sea glass. Scales glittering against the wind. Faces he knew.
His father’s people.
Fear clawed up his spine. His stomach twisted.
Had they found him? Were they sent by…?
He stumbled back from the window, heart pounding. He couldn’t breathe.
Would his father curse Katsuki? Drag him into the deep? Shouto had heard the stories. He’d seen it happen. His father didn’t need to touch you to destroy you.
The dream came again that night.
The water was black, and his father’s voice rolled through it like thunder.
“Return to the sea. Leave the man. Or watch him drown.”
Shouto woke in tears.
He didn’t want to leave.
He didn’t want Katsuki to be hurt.
But could he stay , if it meant risking him?
The storm rolled in fast that evening, loud and cruel against the windows. Katsuki barely looked up from his book when Shouto crawled into bed, silent. The lightning lit his sharp face in flashes. His hand reached out automatically, pulling Shouto in.
Shouto held him close.
Tight. Like it was the last time.
“I love you,” Shouto whispered, the words tasting new. Final. “I learn word. For you.”
Katsuki blinked. “What…?”
Shouto kissed him before he could say more. Soft. Deep. Goodbye .
Later, when Katsuki fell asleep, Shouto watched him.
Memorized him.
Then rose.
The door didn’t creak. The waves were louder than his footsteps. The sea called.
Down at the shore, the water was black and furious, but they were there. Waiting.
His father.
And beside him, the sea witch.
The one who made the deal.
Shouto stepped forward.
And didn’t look back.
Thunder cracked like gunfire overhead.
Katsuki jolted awake, heart pounding, the room lit in a strobe of cold light. For a moment he lay still, listening. But something was wrong.
Too cold. Too quiet.
His arms were empty.
“...Shouto?”
He sat up fast, eyes darting around the darkened room. No silver hair on the pillow. No warmth beside him.
“Shouto!” Katsuki stood, voice louder this time. The blankets were kicked halfway off the bed, like someone had left in a hurry.
He checked the bathroom. The kitchen. The fucking hallway.
Nothing.
Then-
The front door.
Wide open. Rain curling inside in misty fingers, soaking the floor.
Panic hit him like a punch.
He ran. Barefoot, shirtless, down the hill, lungs burning as wind slammed into him. The storm was in full rage now, sky split open with lightning. And through the chaos-
He saw it.
A figure in the waves. Pale, small. Shouto .
And not alone.
There were others, silhouettes with glinting eyes, barely visible in the dark water. Just upper halves above the surface. Still. Watching.
Katsuki’s chest caved in around his heart.
“SHOUTO!” he roared, feet slamming through wet sand.
Shouto gasped and turned. The water pulled at him, dragged him back, but he resisted, swam toward the shore until a crashing wave hurled him forward.
He landed hard, coughing, dragging himself onto the beach.
But-
Katsuki stopped dead in his tracks.
No legs.
Shouto’s lower half shimmered in the stormlight, scales glinting red and white like blood and snow. A powerful tail, thrashing weakly, struggling against the drag of the sea.
He was beautiful. Terrifying. Familiar.
A merman.
Shouto looked up at him with wide, glassy eyes.
“I… sorry,” he whispered. “Not want go….”
Katsuki fell to his knees beside him, soaked through, hands hovering like he didn’t know where to touch. “What the fuck is this…? What’s happening?!”
Shouto smiled. Sad. Small. “I say.. I love you.”
“No- no , don’t say that like it’s the last fucking time-”
“Thank you… for giving home.”
“Shouto-”
The tide surged.
Shouto’s fingers slipped from his grip.
“Shouto!”
A wave rose, towering, furious, then slammed down over the sand, swallowing everything.
When it pulled back, there was nothing left.
Just foam. Rain. The echo of thunder. And Katsuki, sitting on the wet sand, fists clenched, shaking, the word no clawing silently at his throat.
The sea had taken him.
And Katsuki was alone.