Chapter Text
He wakes up in a cell, eyes bleary as the world comes into focus around him. The skin around his wrists burn, raw from where he'd struggled against Harumichi's ice.
The ice— Rui.
Rui.
"Rui!" he screams out, searching. The last thing he remembers is Rui, eyes lifeless, body still on that horrible marble floor. Red seeping from his wounds. Tsukasa barely recognizes his own voice, hoarse and rough from overuse. He must be crying, because the world blurs again as warm tears run down his face. "Rui!" He tries again, and this time, a guard— one that he recognizes, kicks at the bars of his cell.
Tsukasa doesn't even flinch.
"Shut. Up!" the guard snarls. "God. Alan. Can we just knock him back out?"
The sound of something being dragged across the floor follows. "I've got a better idea," Alan sneers, and then the bars of his cell are swung open. What follows is a long, dark mass being heaved through the door, dropped at Tsukasa's feet as if it were a sack of garbage.
Tsukasa remembers how Rui's scales would glow, smatterings of bright teal bright in the darkness of the water. They look dull now, flickering in the dim lighting of the dungeons. He lurches forward, stomach churning. He's stopped by the chains around his wrists, digging into his sore skin.
"There's your demon, you demon-fucking commoner," he sneers. "Couldn't even wait for Commander Toya's body to cool, could you?"
He's talking, but Tsukasa can't hear any of it. His ears ring as he stares blankle down at the body before him. He can make out a head of tangled purple hair, a single teal streak in it. He watches it, checking for movement as he strains against the cuffs.
The lack of response seems to tick the guard off, and then theres a bucket of water being splashed on him. It smells old and musty— probably leftover from mopping.
Rui gasps as the water hits him, gills opening as he finally breathes. His teal scales glow, and he coughs. It's clearly not good for him, the polluted, filthy water, but it's enough to keep him alive.
"Remind me why we need to keep this one alive?"
"The scales lose their magic as soon as they're dead. You gotta keep them alive if you want to turn any kind of profit."
The thought— of Rui bring stripped of his scales, one by one, sickens Tsukasa to his core. Rui doesn't react to the news, instead shivering as he curls away from Tsukasa, panting. His canines are long and sharp, scraping against the ground as he presses his face away from Tsukasa.
"Stay away," Rui pants, his voice sounding melodic even in this pained state.
Tsukasa obviously isn't going to listen, he pushes closer, blood streaking down his wrists in warm rivulets. Rui's pupils narrow, and on instinct, he twitches closer, before flinching away with a sharp jerk.
Somewhere in the distance, two bodies hit the ground.
"Please—" Rui's voice cracks, but still the sound of it is like heaven. "Please— Tsukasa-kun… I— your… hah…" Rui trails off, and Tsukasa watches with morbid fascination as drool slips out of the siren's jaw, trailing off of those long teeth before Rui snaps his mouth shut and swallows. Hard.
Realization fills Tsukasa, it tastes like hope. "My blood," he whispers. "Rui— my blood," he says again, urgency in his voice.
Rui shakes his head, tears slipping out of those beautiful, beautiful eyes as he grits his teeth, veins popping along his jaw. More saliva drips onto the ground.
"Why?" Tsukasa asks, his voice giving out as he says the word. Rui sobs, the sound hurts more than anything.
For a long while, there's only the sound of Rui's crying. The guards are nowhere to be seen— but Tsukasa couldn't care less about where they were. All his mind is filled with is Rui, who's still bleeding, who's skin is still burned. Who's refusing to drink even a drop of Tsukasa's blood even if it would heal him, even though his body hungers for it.
Rui's eyes close as he presses his forehead into the stone floor. "I'm… a monster."
"You're not—"
"I am— Tsukasa— siren's… we… do you know what we eat?" A dry laugh follows. "Blood— humans, fish, animals. You know there are sirens who hunt humans for sport?" His voice breaks off into a sob. "I thought… I thought I could get away from it. I thought— if I were just human. I could be with you— you— you would want me. Or— if I couldn't be human— if I just. If you never saw me like this— if you never knew me like this— then we could— I could— fuck."
Tsukasa swallows, the lump in his throat painful. He can't bear to hear Rui talk like this, like he isn't beautiful, like it mattered one bit what he was, what he looked like, what he ate. Like Tsukasa cared about any of it beyond it being Rui.
"I'm so. selfish." Rui whimpers, "You're— hah— you're hurt. You're bleeding— I… I love you—" he chokes on the words, gasping, running out of air, but he continues. "I love you so much," he sobs, "And I thought— I thought I could be with you— But I can't— you're… so…" another gasp, "… like the sun. Like light in the darkness— I just… wanted to see you again. I—" he coughs, inhaling desperately at the air that won't provide him breath. "I love you. You're hurt. And I… want… to…" His eyes dart over to Tsukasa's bloodied hands, gasping sharply, twitching with want, with need.
Tsukasa doesn't give a flying fuck what Rui thinks he should want.
Honestly, he's a little bit mad about it. How dare Rui come into his life— smile his way into Tsukasa's heart, kiss him and hug him and fill him with all things that were warm and loving and beautiful— and then dare to even imply that he was wrong for doing so? Blasphemy. Heresy. Utter fucking bullshit.
Without giving it a second thought, or even a first one, Tsukasa bites down on his lip, hard. And then, because Rui is weak and dying and being an absolute idiot, and because Tsukasa loves him so, so much, he presses the warm, pulsing iron to Rui's stupid, bullshit-spewing mouth.
Rui makes one small noise of protest, but as the blood fills his mouth, he moans, tongue flicking out to lap greedily at Tsukasa's bleeding lip. When he realizes what he's doing, he pulls back, but Tsukasa doesn't give him a chance, muffling any sound of protest Rui makes, pressing closer.
His arms strain behind him, a clawed hand comes up to cup his face. Capable of breaking stone and impossibly gentle. Tsukasa nuzzles close to it, feeling a violent sort of affection overhwlem him. He nips at Rui's lips, Rui nips back. His mouth is bleeding some more— maybe Tsukasa is a little bit of a masochist, because the pain sends a warm shiver up his spine that makes him whimper into the kiss.
He doesn't know how long they kiss for, Rui gulping hungrily at the scarlet that drips from Tsukasa's broken skin. He doesn't even know if the guards are watching them— but he really wouldn't care. When he pulls away, Rui's eyes are nothing but a thin ring of yellow, the rest of it a deep black.
His lips have stopped bleeding, probably thanks to all the saliva they both slobbered over the wound. It throbs when he speaks, and yeah, he's definitely a bit of a masochist.
"Do you think that I, the great Tsukasa Tenma, would care what you are?" he says, and Rui blinks at him, for once stunned stupid. A smirk makes its way across Tsukasa's face, his lip starts bleeding again. "Because you're right, I do care."
"I— what?"
Tsukasa licks at the blood on his lip, watching with satisfaction as Rui's eyes follow the action. "I care that you only like to eat meat," he says, "I care that your scales have a purple sheen to them, I care that your teal scales glow a little, because it means you're alive."
Rui's eyes widen, breath hitching. His face goes pink as he stares at Tsukasa, blood smeared all over his parted mouth.
"I care because you're so much… longer than I remember, and I wish I was there to see it happen, I care that you have claws that can break gemstones, but you touch me with all the gentleness in the world. I like that your eyes have slits in them, like a cat. I like how your voice sounds in this form, I like your tail, I like the webs between your fingers. I like your teeth— I want to feel them against my—"
A hand covers his mouth before he can continue, and when he peeks at Rui, he's beet red. Other hand covering the bottom of his face. His eyes are blown completely wide, and he looks like a complete mess— the wounds on his torso have long stitched themselves together, the glowing teal scales back to shining along his body like stars. His ears are pressed back, webbed and fin-like and they're— are they glowing?
Tsukasa kisses the hand on his mouth, smiling when it twitches, claws grazing ever so slightly against his skin, but not cutting. "I like how your ears glow when you're embarassed." He says, and a noise comes out of Rui's throat— like the trill of a flute.
"I love every part of you," Tsukasa says, pressing another kiss to Rui's lips. "Now. Get me out of these restraints."
As it turns out, the guards had fainted way before they started making out, which was a little bit of a relief for Tsukasa, because he didn't look forward to facing his coworkers again if they were privy to the entire thing. Also, they had fainted because Akito and Toya had managed to destroy the gemstone— and actually, the entire capital had fainted because of that. Seems like breaking long-lasting mind-control magic required some degree of unconciousness, who knew?
Rui had kicked at the guards and dumped a bucket of much fouller water on them after exploding the bars of their cell. Tsukasa didn't stop him.
After the initial chaos of thousands of people all fainting at the same time— and thank god for Emu pulling the unlucky few who fainted in dangerous spots out at lightning fast speed— the capital eventually rearranged itself.
With the enchantments gone from the capital, Minori had led a group of fairies back to explain the situation to the humans. They took the news a lot better than when it came from Emu, who had an huge smile on her face while shouting from the top of a dragon. There were still a few stragglers who hated demons and insisted they be banished or something, but as a whole— the enchantments really did seem to be necessary, because a majority of people had fond memories of demons and were elated to reunite with their friends.
Apparently, the king had no idea any of this was happening— it'd been entirely planned by the heads of a few noble houses, with the three major ones doing most of the work. There were varying reasons; political power, generally being the worst, and generally being pushovers. The King was impeached almost immediately, being incompetent enough to have completely missed basically everything. Seriously, what was he doing this whole time? And was succeeded by his only daughter, Ichika Hoshino, who was surprisingly down-to-earth and easy to reason with.
It'd been a piece of cake to convince her to arrest Toya's shitty father, that rude lady from the Asahina house, and the clueless Hinomori couple who'd just gone along with it because it was easier than arguing. Their children succeeded their houses, though Mafuyu Asahina stepped down after three days, leaving the entire estate in the hands of her father before running off with an entirely white-clad figure.
Queen Hoshino then gave the Tenma's the status of nobles— by marrying Saki, a servant girl named Honami, and the younger Hinomori sister— which Tsukasa was still completely shocked about, even if he bawled his eyes out at the wedding. Now that his sister was… one of four queens, it was much easier to deal with (fire) all of the rude knights, which Toya was happy to comply with.
Before he knew it, a year had passed, with the kingdom settling into an era of peace and prosperity previously thought impossible to achieve.
"Ehhh? But Onii-chan! I wanted to hear more about you and Rui!" Saki whines, setting her teacup down with a pout. "It's so romantic! i can't believe he's the same Rui-kun from back then!"
Rui laughs at his side, clad in the robes of the royal sorcerer. After the fireball incident he'd made it a mission to learn about all the elemental magic. He apparently was not aware that fire was different from light, which made sense, since he spent most of his time in the water looking for ways to become human. After researching intensely for a week, he'd emerged with flaming birds and all sorts of other weird magic that had gotten him arrested (again).
At that point, the Queens decided it was probably better to put him in a position where they could keep an eye on him, and give him plenty of outlets for the frankly insane feats of magic he was performing on a regular basis.
"Well, Saki-kun… After I released Tsukasa from those awful restraints we—"
"— THANK YOU FOR THE TEA!" Tsukasa interrupts, before jumping up and dragging Rui behind him. Saki cackled in the background.
"See you tomorrow!" she snickered. These two would be the death of him someday.
Rui is still laughing when they get to the harbour, waving at the locals who had grown to recognize the siren that always accompanied Tsukasa. They'd been a bit terrified at first, but with all the changes happening, had quickly accepted Rui's presence. Sometimes he would even bring them rare fish when he was out for a swim— which they were always delighted by.
Tsukasa fidgets as they walk along the shore, the harbour growing distant behind them. "Rui… are you sure this is going to work?" He toes off his shoes and socks and leaves them on a rock.
Rui grins. "I would never put your safety at risk, love."
"Hmph. Well. Okay," Tsukasa says through his lips, twisted with embarassment. He steps into the water, and Rui follows, completely naked— his transformation undoes itself, hands shifting into claws, legs fusing and growing into one long tail. He reaches out a hand to Tsukasa with a sharp grin, guiding him into the water.
Tsukasa takes a deep breath— just in case— and dunks his head in, eyes squeezed shut. Rui prods at him, and he opens one eye, shocked at how clear everything is.
A little less suspicious, now, he exhales… and inhales. His jaw drops open, he does it again— he's breathing! Underwater!
His limbs are all human-like, but when he brings a hand up to his neck, he realizes there are gills there.
"Rui! This is amazing!" he exclaims, turning to the other man; even his voice is travels underwater. Rui's eyes sparkle with joy, his grin soft and loving as he pulls Tsukasa in for a kiss, before lacing their hands together and bringing them deeper into the sea.
It's beautiful, the farther they are from the coast the more beautiful it is. Vibrant corals that teem with life, fish of all shapes and colours swimming among the watery fauna. He touches something called an anemone, screaming when it reacts to his touch.
"Don't disturb the fishes, Tsukasa," Rui scolds— his voice is even lovelier in his siren form, low and song-like. Tsukasa blinks with surprise with a group of orange-white fish swim out of the thing he poked, swimming around frantically. He giggles, Rui pulls him into a hug, peppering kisses along his neck. "I've always wanted to show you this," he murmurs. "You look beautiful."
"Like you're one to talk," Tsukasa shoots back, bringing a hand up caress Rui's cheek. "I love seeing you like this."
As usual, Rui flushes red, his ear-fins trembling as they begin to glow. His throat does that trill thing that sounds even better in the water— this is how sailors drowned to their deaths, they must've been following that sound.
He presses another kiss to Rui's mouth, feeling the trill thrum through his body. Rui pulls away, soft and reverent, pulling Tsukasa deeper through the water.
If this entire thing was just a ploy to drown Tsukasa to his death, he thinks it would've been worth it.
But even better than that, it isn't. Rui takes him deep in the ocean, as far as they can go before they "run into siren territory". He gestures to a deep drop in the sea floor, that seems to go on forever into an abyss of darkness.
"Is that where you grew up?" he asks, peering as close to the ledge as Rui will let him go.
Rui nods. "And it's boring," he says, "I guess the fish are cool, but really, the company is so dreadful," his eyes flash playfully over to Tsukasa, "unlike my current company, of course."
Tsukasa rolls his eyes, but his heart warms like it always does when Rui flirts with him. You'd think that after a year he'd be used to it by now, but no— the other man would surprise him, catch him off guard. "Well. That's a given," Tsukasa says, instead of the embarassing whine he wants to say instead.
They swim along the ocean floor, digging up seashells and watching as fish swim by. Tsukasa can see the shadow of fishing boats above them. Rui teaches him how to blow ring-shaped bubbles, and they play a game where Tsukasa blows rings and Rui swims through them, elegant and graceful as he weaves in and out of the nonsensical patterns.
He could watch Rui swim for hours— the strong flicks of his tail, the way he cuts through the water, spinning as his long tail trails behind him, scales glittering from the dappled sunlight above.
Tsukasa tries to mimic Rui, but all he accomplishes is flailing about in a sort of undignified manner that he doesn't care to repeat. Rui laughs at his attempts, and if it were anyone else, Tsukasa might feel offended.
They race (a pointless game), scare schools of fish, and watch a hermit crab tug a shell across the sandy floor.
Eventually, the sun sets, and they watch as the water turns beautiful shades of orange and pink. Rui turns to him, whispers. "I used to watch the sunset and think of you."
Tsukasa's heart thuds in his chest— sometimes he loved Rui so much it ached, and he pulls the other close to him, breathing in the scent of ocean and flowers that he's glad still remains under the water.
When the sun sets, they look at the stars from the sea floor, those pinpricks of light dancing as the wobbly surface of the sea distorted them this way and that. Rui hums a silly song, and Tsukasa laughs.
Rui pulls hiim in for another kiss, licking at Tsukasa's mouth hungrily, even when there's no blood. Tsukasa hums into the kiss, swallowing every pleased noise Rui makes against his lips as the other does the same.
When he pulls away, it's to Rui's softly glowing eyes staring at him, soft at the corners as his ears shine a soft blue. His inky black scales shine like the night sky, the smattering of glowing teal scales more beautiful than the night sky itself.
There's another scale, twisted into the shape of a ring— gold finishes the circle where the scale couldn't reach. Tsukasa blinks at it.
"Did you know," Rui clears his throat, "that giving a scale to someone is a sign of courtship?"
Tsukasa's hand flies to the necklace around his throat, where the scale Rui had given him when they were young rests. "You—"
Yellow eyes, gentle, clawed hands, the scent of flowers and the salty sea. Rui presses his lips to the back of Tsukasa's hand, trembling a little bit as he held the ring out towards him. "I've already staked my claim in the sea— I… I thought… if I could… on land as well."
His usual eloquence seems to leave him as he searches for words, ears glowing brighter with embarassment. Tsukasa thinks he's going to cry— and actually he's already crying.
The taste of the salt in the water makes Rui panic. "You don't have to—"
"Yes," Tsukasa laughs, feeling like he could burst with the happiness that fills him. He must have the stupidest grin on his face right now, but he can't help himself. Rui wraps his tail around him, eyes wide.
"Really?"
Tsukasa bumps their foreheads together, meeting Rui's startles eyes with his own— he wishes he could show him how happy he is, wishes he could press his feelings into the other's chest with kisses and soft words. He nods.
"Really."
The ring slips onto his finger, warm and glowing softly. Before even a second passes, they're kissing again, deep, hands tangled in each other's hair, Rui wrapped tightly around him. It's warm and perfect, he hopes Rui can hear his thoughts, if not, he'll just have to tell him.
"I love you," he whispers, voice cracking on a happy sob, he kisses the scales along Rui's cheeks. "All of you."
Rui nuzzles into him. "I love you too," he answers, and when he tangles their hands together, claws and all, Tsukasa thinks that there isn't a thing in the world that could feel more like home.