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I. The Way Suo Loves in the Middle of the Night
This happen before chapter 3 of main story
The castle had fallen into that special kind of silence that only came after midnight.
No footsteps echoed through the corridors. No voices carried from the guard posts. Even the violet sky beyond the window seemed to hold its breath, as if the world itself had decided to pause.
Suo did not sleep.
He never truly did — not anymore, not for many years. Sleep was a luxury he had traded for vigilance long before he wore the crown. His body had learned to rest in fragments, shallow and watchful, always ready to wake at the smallest disturbance.
But now —
Now he stayed.
Not because he had to. Not because duty demanded it.
Because Nirei was beside him.
Suo lay on his side, propped on one elbow, watching the slow rise and fall of the prince's breathing. The room was dark, lit only by the faint glow of dying embers in the hearth, but he didn't need light to see him.
He had already memorized every detail.
The way Nirei's golden hair spread across the pillow like spilled sunlight. The soft curve of his cheek, still carrying a faint flush from sleep. The small, content sound he made whenever he shifted — something between a sigh and a hum, so quiet that anyone else would have missed it.
Suo never missed it.
How long have I been watching him?
The question surfaced without warning. He didn't have an answer. Minutes, perhaps. Hours. Time had stopped mattering somewhere between the softness of Nirei's breathing and the warmth radiating from his skin.
This is foolish.
The thought came from somewhere old — somewhere that still remembered logic, still remembered distance, still remembered the walls he had built around himself for centuries.
He should leave. Should return to his own chambers. Should maintain the boundary that separated the Demon King from everyone else.
But Nirei's leg had kicked the blanket loose again.
Suo exhaled — a quiet sound, almost a laugh — and reached for the fabric. He pulled it up slowly, carefully, tucking it around Nirei's shoulders without disturbing him. The movement was practiced now. He had done this before. Many times.
When did I start doing this?
He couldn't remember the first time. Couldn't pinpoint the moment when watching Nirei sleep had become part of his night. It had simply… happened. A habit formed without intention, repeated until it felt as natural as breathing.
Dangerous.
But he didn't stop.
His hand lingered on the blanket for a moment longer than necessary. Then, almost without permission, his fingers drifted upward — brushing against Nirei's hair.
Soft.
So impossibly soft.
Suo had touched many things in his long life. Swords. Crowns. Stone. Blood. None of them had ever felt like this.
He traced the line of Nirei's hair, from temple to cheek, light as a whisper. The prince didn't stir. His breathing remained steady, deep, utterly trusting.
He doesn't know I'm watching.
The thought should have unsettled him. Instead, it made something in his chest tighten — not painfully, but warmly. Like embers stirring back to life after being left untouched for too long.
"Suo…"
The whisper came so softly that Suo almost thought he had imagined it.
He froze.
Nirei's lips had parted slightly, the sound slipping out between breaths. Not a call. Not a question. Just a name — spoken in sleep, shaped by something deeper than consciousness.
He's dreaming of me.
The realization struck like lightning — silent, sudden, electric.
Suo's heart stopped.
Then — it raced.
For the first time in hundreds of years, the Demon King's heart raced.
Not from battle. Not from fear. Not from any threat he could name or fight.
From a whisper.
From his name, spoken softly in the dark, by someone who didn't even know he was listening.
This is what love feels like.
The understanding settled quietly, not as a revelation, but as a confirmation. He had known it before — in fragments, in moments, in the way he couldn't look away from Nirei's smile. But here, in the silence of the night, with nothing but the sound of breathing between them, it became undeniable.
I love him.
Not as an observation. Not as a conclusion.
As a truth.
Suo leaned down.
Slowly. Carefully. Giving himself every chance to stop — but knowing, even as he moved, that he wouldn't.
His lips brushed against Nirei's forehead.
Soft. Brief. Almost shy.
A kiss that asked for nothing. A kiss that gave everything.
"I'm here," he breathed against Nirei's skin, the words so quiet they barely existed. "Always."
Nirei didn't wake.
But his lips curved — just slightly — into the faintest smile.
As if, even in dreams, he had heard.
---
Suo did not move after that.
He stayed where he was, propped on one elbow, watching the prince sleep. The embers in the hearth continued to fade, casting longer shadows across the room, but he paid them no attention.
His hand found Nirei's beneath the blanket.
Not holding. Just… resting. Palm against palm, fingers barely touching. A connection so light it could have been accidental.
It wasn't.
How many nights have I wasted?
The question came unbidden. How many centuries had he spent alone in this castle, believing that solitude was strength, that distance was protection? How many nights had he stared at these same walls, feeling nothing but the weight of his crown?
And now —
Now he couldn't imagine sleeping anywhere else.
Nirei shifted, rolling slightly toward him without waking. His face pressed closer, seeking warmth instinctively, and Suo's arm moved before he could think — wrapping around him, pulling him in, until the prince's head rested against his chest.
This is where he belongs.
The thought was selfish. Irrational. Entirely unlike him.
And he didn't care.
Suo pressed another kiss to the top of Nirei's head. Then another. Soft. Lingering. As if he was trying to memorize the feeling, to seal it into his memory forever.
"I don't deserve you," he whispered.
It was the most honest thing he had ever said.
But Nirei — asleep, trusting, impossibly warm — only nestled closer.
As if to say:
You don't have to deserve me.
I'm already here.
Time moving
Outside, the violet sky began to lighten.
Morning would come soon. The castle would wake. Duties would return, and the Demon King would once again become the ruler his people needed.
But for now —
For now, there was only this.
Suo's fingers traced slow circles against Nirei's back. His eyes grew heavy, not from exhaustion, but from something softer — something that felt almost like peace.
He had not slept properly in centuries.
But tonight —
Tonight, he closed his eyes.
And for the first time in hundreds of years, Suo dreamed.
The servants noticed it the next morning — the way their king seemed… different. Lighter. Not in expression, not in posture, but in something unnameable.
No one dared to ask why.
But those who passed the prince's room saw the door left slightly ajar — and through the gap, the shadow of two figures still tangled together, unwilling to part.
The Demon King, who never slept, had finally found a reason to rest.
And his name was Nirei.
____________________________________________________
II. The Letter That Was Never Sent
This happen after chapter 3 in the main story
The castle slept.
Suo should have been sleeping too — or at least pretending to, the way he had done for centuries. Resting his eyes while his mind remained sharp, always watching, always waiting.
But tonight, he sat at his desk.
A single candle burned beside him, its flame small and steady, casting just enough light to write by. The rest of the room lay in shadow — the bookshelves, the maps, the throne of obsidian that waited for him each morning. All of it faded into darkness.
Only the paper before him existed.
Suo dipped his pen into the inkwell.
Then — he hesitated.
What am I doing?
The question surfaced quietly, not as accusation, but as genuine uncertainty. He had written countless letters in his life. Commands. Declarations. Threats disguised as diplomacy. Each one had been precise, deliberate, crafted with the care of a ruler who understood the weight of words.
But this —
This was different.
He had no audience for this letter. No purpose. No strategy.
Only the need to write.
His hand moved before his mind could stop it.
"Nirei."
Just the name. Written alone at the top of the page, as if it were enough to hold everything he couldn't say.
Suo stared at it.
The ink was still wet, glistening in the candlelight. One word. One name. And already, his chest felt tighter than it should.
When did you become this important?
He didn't know the answer. Couldn't trace it back to a single moment, a single conversation, a single kiss. It had happened slowly — too slowly to notice, then all at once, until he couldn't remember what it felt like before.
Before Nirei.
Before warmth.
Before the silence of his castle had started to feel empty rather than peaceful.
Suo's pen touched the paper again.
"I did not mean to fall in love with you."
The words came out blunt. Honest. Nothing like the careful sentences he used in court.
"It was never part of any plan. You were supposed to be an observation — a curiosity, nothing more. A human without magic. A prince without power. Something to pass the time until the war resumed its course."
He paused.
The candle flickered.
"But you stayed."
"Not because you had to. Not because I forced you. You stayed because you chose to — again and again, in ways I could not predict and could not prevent."
"And somewhere between your honesty and your stubbornness and the way you look at me like I am not a monster — "
His hand trembled.
Just slightly.
Enough that the next letter came out crooked.
"— I stopped watching you."
"And started waiting for you."
Suo set down his pen.
The room felt smaller now. Or perhaps larger. He couldn't tell. All he knew was that the words on the page were more exposed than he had ever allowed himself to be — and no one would ever read them.
That was the point.
This letter was not for Nirei.
It was for himself. A confession with no witness. A truth he could finally shape into words, knowing they would never leave this desk.
He picked up the pen again.
"You asked me once if I liked you."
"I said the word was too small."
"I meant it."
"Love is not the right word either — not because I feel less, but because what I feel does not fit into something so simple. Love is for poets. Love is for stories. What I feel for you is not a story."
"It is the reason I sleep now."
"The reason I wake before dawn, just to watch you breathe."
"The reason I have started to hope — after centuries of knowing better — that perhaps the world does not have to remain as cruel as I believed."
His eyes burned.
Not from exhaustion.
From something he had not felt in so long he had almost forgotten its name.
Tenderness.
"I am afraid."
He wrote the words quickly, before he could stop himself.
"Not of war. Not of death. I have faced both too many times to fear them anymore."
"I am afraid of losing you."
"Of waking up one morning and finding that you have gone — not because I pushed you away, but because the world finally convinced you that I am not worth staying for."
"I am afraid that one day, you will see me the way others see me."
"As a king. A weapon. A monster."
"And you will realize that you made a mistake."
The ink blurred.
Suo blinked once, twice, and realized — distantly, almost scientifically — that his vision had grown wet.
He had not cried in centuries.
He had forgotten how it felt.
He did not wipe the tears away.
He let them fall, silent and warm, onto the page. They landed beside his words, softening the ink, smudging the edges of his confession.
Let them.
Let the paper remember what I cannot say aloud.
He wrote the final lines slowly, carefully, as if each word cost him something irreplaceable.
"I love you, Nirei."
"Not because you are kind — though you are."
"Not because you are brave — though you are braver than anyone I have ever known."
"I love you because you make me want to be better."
"Because when I am with you, I forget that I was taught to be alone."
"Because you looked at a demon and saw a person."
"And now — "
He stopped.
Took a breath.
"And now, I want to be the person you see."
"Every day. For as long as you will have me."
"That is not a threat."
"That is a promise."
Suo set down the pen for the final time.
The candle had burned low, its flame wavering, close to extinction. Outside, the violet sky had begun to lighten. Morning would come soon.
He looked at the letter.
Pages of it. Lines of it. A confession written in midnight ink, sealed with tears he had not shed in centuries.
No one will ever read this.
The thought should have brought relief. Instead, it brought something closer to grief.
He folded the pages slowly.
Once. Twice. Until they fit into a small square that could fit inside his palm.
Then — he opened the drawer of his desk.
The drawer where he kept nothing of value. Old reports. Broken seals. Things that had outlived their purpose.
He placed the letter inside.
Closed the drawer.
And sat in silence as the candle died.
—------
One day, as if fate itself had willed it, Nirei found the letter.
He hadn't been looking for anything. Suo had asked him to retrieve a map from the desk — something about border patrols, about adjustments to the ceasefire agreement. Nirei had nodded, walked to the study, and opened the drawer without thinking.
The letter was on top.
Unmarked. Unsealed. Folded carefully, as if someone had handled it many times.
What's this?
Nirei hesitated.
It wasn't his. He shouldn't read it. Every instinct taught him to close the drawer, to pretend he had seen nothing, to respect whatever privacy the Demon King still maintained.
But —
His name was written on the first page.
Just his name. Alone at the top, in handwriting he recognized immediately.
Suo's.
Nirei's heart stopped.
Then — without permission, without decision — his fingers unfolded the paper.
He read the first line.
His breath caught.
He read the second.
And the third.
Nirei's eyes widened.
He kept reading.
Page after page. Line after line. Words that Suo had never spoken aloud — confessions that the Demon King had hidden behind composure and silence and smiles that revealed nothing.
By the time he reached the end, Nirei's hands were shaking.
Not from cold. Not from fear.
From something too large to name.
He heard footsteps in the corridor.
Suo's footsteps — he knew them now, could recognize them among a hundred others. Calm. Measured. Unhurried.
Nirei folded the letter quickly — but not quickly enough.
The door opened.
Suo stepped inside.
And stopped.
His gaze moved from Nirei's face to the paper in his hands — to the familiar fold, the unmarked cover, the way Nirei's fingers trembled around its edges.
Suo's expression did not change.
But something behind his eyes did.
"You read it."
Not a question.
Nirei swallowed.
"I — I didn't mean to — I was looking for the map, and it was open, and I saw my name — "
"You read it."
Suo's voice was quiet. Flat. Unreadable.
Nirei nodded slowly.
"…Yes."
Silence.
The kind of silence that could crush kingdoms.
Then —
Suo turned away.
Not dramatically. Not angrily. Just… turned.
And then — he walked toward the window.
Nirei blinked. "Suo?"
Suo didn't answer. His hand reached for the windowsill. His posture was stiff, his shoulders tense, and — was that panic in his movements?
"Suo, what are you — "
Suo climbed onto the windowsill.
Nirei's brain stopped. "Wait — WAIT — "
But it was too late.
Suo jumped.
From the second-floor window.
Straight into the open air.
Nirei ran to the window and looked down, heart pounding —
Only to see Suo floating gracefully downward, his dark wings spread wide, catching the violet light. He landed on the courtyard below as softly as a falling leaf. Composed. Elegant.
Completely unharmed.
And then — he started walking away. Fast.
"Did he just — " Nirei stared in disbelief. "Did the Demon King just FLEE from me?!"
His face flushed — not from embarrassment this time, but from sheer, burning determination.
"Oh no you don't."
Nirei climbed onto the windowsill.
He didn't have wings.
He didn't have magic strong enough to slow his fall.
He didn't have a plan.
But he had anger. And embarrassment. And a letter that said I love you in approximately may different ways.
So he jumped.
"NIREI — !"
Suo's voice cracked.
For the first time in centuries, the Demon King screamed.
He saw the small figure falling from the second floor — golden hair flying, arms flailing, eyes squeezed shut — and every logical thought in his mind evaporated.
Suo moved faster than he had ever moved in his life.
His wings snapped open. His body launched forward. His arms reached out —
And caught Nirei.
Barely.
They tumbled together across the courtyard grass, rolling twice before coming to a stop. Suo's back hit the ground first, his wings cushioning the impact, his arms wrapped so tightly around Nirei that he could feel the prince's heartbeat against his own chest.
Panting. Shaking. Terrified.
"You — " Suo's voice was hoarse. "You absolute — reckless — "
Nirei lifted his head from Suo's chest.
His face was flushed. His hair was full of grass. There was a small scratch on his cheek from a branch.
And he was grinning.
"Got you."
Suo stared at him.
"…What?"
"I caught you," Nirei said, still grinning, still breathless.
He placed both hands on Suo's chest — right over his still-racing heart.
Suo opened his mouth.
Closed it.
Opened it again.
No words came out.
His face — the face of the Demon King, the ruler of the demon realm, the man who had faced armies without flinching — turned a deep, unmistakable red.
Suo lay there on the grass, still pinned beneath Nirei, still red-faced, still refusing to meet his eyes.
His wings had folded back against his shoulders, dark and elegant, but his composure — the carefully crafted mask he had worn for centuries — was nowhere to be found.
Gone.
Shattered.
Because of a letter. A window. And a human prince who refused to let him escape.
"…You're thinking too much," Nirei said softly.
Suo's eye flickered toward him — then away.
"I am not thinking at all," he lied.
"You are. I can tell."
"How?"
"Because your left hand is trembling."
Suo stilled.
He looked down.
His left hand — the one hidden beneath his wing, the one Nirei shouldn't have been able to see — was indeed trembling. Just slightly. Barely noticeable.
How did he —
"I know you," Nirei said, as if reading his thoughts. "I know the way you breathe when you're scared. I know the way your mana shifts when you're trying to hide something."
He placed his hand over Suo's heart.
"And I know that your heart is racing right now."
Suo swallowed.
"…That is a normal physiological response to — "
"Suo."
Nirei's voice was gentle. Not teasing. Not playful.
Just… knowing.
"You don't have to pretend with me."
Suo's throat tightened.
"I am not — "
"You are."
"Nirei — "
"You wrote a letter because you couldn't say it out loud." Nirei's thumb traced slow circles over Suo's chest. "You kept it because you couldn't throw it away. You left it where I might find it because some part of you wanted me to know."
He paused.
"And then you jumped out a window because you were terrified of what I would say."
Suo closed his eye.
"…That is a very detailed analysis," he murmured.
"I know you," Nirei repeated. "That's what love is, isn't it? Knowing someone so well that you can see right through all their walls."
Silence.
The wind moved softly through the courtyard, carrying the distant sound of Choji's laughter fading into the castle.
Suo's hand — the trembling one — slowly rose.
His fingers found Nirei's wrist. Held it. Gently.
"…I am not used to this," he admitted.
"Used to what?"
"Being seen."
Nirei's heart ached.
"I know," he whispered.
"For centuries, I have been the Demon King. The one who rules. The one who protects. The one who cannot afford weakness." Suo's voice was low, barely audible. "I forgot what it felt like to be… just a person."
"You're not just a person."
"No?"
"You're my person."
Suo's eye opened.
He looked at Nirei — really looked — and saw no judgment. No pity. No fear.
Just love.
Warm. Steady. Unafraid.
They didn't move for a long time.
The grass was soft beneath them. The morning air was cool, carrying the faint scent of night-blooming flowers from the garden. Somewhere above, a window creaked shut — probably Togame, finally dragging Choji away from the scene.
But neither Suo nor Nirei paid any attention.
They lay there, tangled together, breathing the same air, feeling the same warmth.
Until finally —
"…We should probably get up," Nirei murmured.
"No."
"Suo, the guards are watching."
"Let them watch."
"Your reputation — "
"Is already ruined," Suo said flatly. "I jumped out a window. There is no recovery from that."
Nirei snorted.
"Fair point."
He pushed himself up slowly, reluctantly, his body protesting the loss of warmth. Suo's arms loosened around him — but didn't let go completely.
Not yet.
Nirei looked down at himself.
Grass stains dotted his sleeves. Dirt clung to his knees. There was a small tear near his collar where a branch had caught him during the fall.
"I look terrible," he announced.
Suo sat up slowly, his wings folding neatly against his back. His gaze swept over Nirei — from the grass in his golden hair to the scratch on his cheek to the torn fabric at his shoulder.
"You look like you fell from a window," Suo said.
"Because I DID fall from a window."
"You jumped."
"Because YOU jumped first!"
Suo's lips twitched.
He reached out — slowly, deliberately — and began brushing the dirt from Nirei's shoulders.
Nirei froze.
"…What are you doing?"
"Cleaning you."
"I can clean myself — "
"You are doing it wrong."
"It's just dirt — "
"Be still."
Suo's hands moved with unexpected gentleness. He brushed the grass from Nirei's hair first — fingers combing through the golden strands with a care that made Nirei's heart stutter. Then he smoothed the wrinkles from Nirei's collar, pressed down the torn fabric as if he could will it back together, and dusted the remaining dirt from his sleeves.
"There," Suo said quietly.
His hands lingered on Nirei's shoulders.
"Better."
Nirei stared at him.
"…You're still covered in grass too, you know."
"I am the Demon King. I am allowed to be covered in grass."
"That's not how it works."
"It is now. I am changing the law."
Nirei laughed — bright and warm — and reached out to brush a leaf from Suo's dark hair.
"There," he echoed softly. "Now we're even."
Suo caught his wrist.
Not tightly. Just… held it.
His thumb traced small circles over Nirei's pulse point, where his heartbeat still raced from the fall — or perhaps from something else entirely.
"…You are still looking at me like that," Suo said.
"Like what?"
"Like you see something I cannot hide."
Nirei smiled.
"That's because I do."
Silence fell between them — not awkward, not tense. Just… full.
The kind of silence that didn't need to be filled.
But Nirei wanted to fill it anyway.
"I want to write you a letter back," he said.
Suo blinked. "What?"
"A letter. To answer yours."
"You — you don't have to — "
"I know I don't have to." Nirei smiled. "But I want to."
He shifted, sitting up straighter, his hand still resting on Suo's chest — right over his heart, which was still beating too fast.
"But before I write it… I want to say it first."
"Say what?"
Nirei leaned down.
His lips brushed against Suo's ear — close enough that his breath stirred Suo's dark hair.
"I love you, Suo."
Soft.
Clear.
Certain.
"Not because of the letter. Not because you jumped out a window — though that was very funny."
Suo let out a strangled laugh.
"I love you because you stayed. Because you taught me magic when no one else believed I could learn. Because you looked at a failure of a prince and saw someone worth keeping."
Nirei pulled back just enough to meet Suo's eye.
"I love you because you're you. Even when you're scared. Even when you're hiding. Even when you pretend you don't feel anything."
He kissed the corner of Suo's mouth.
"I love you. And I'm not going anywhere."
Suo's breath caught.
His hand — still holding Nirei's wrist — trembled.
"…You," he started. Stopped. Swallowed. "You say that so easily."
"Because it's easy to say the truth."
"It has never been easy for me."
"I know." Nirei's thumb brushed across Suo's knuckles. "That's why I'm saying it enough for both of us. Until it becomes easy for you too."
Suo stared at him.
At the grass still clinging to his golden hair. At the small scratch on his cheek. At the smile that had somehow, impossibly, become the center of his entire world.
"…I love you," Suo whispered.
"I know."
"I love you so much it terrifies me."
"I know that too."
Nirei leaned forward and pressed his forehead against Suo's.
"But you don't have to be terrified anymore. I'm here. I'm staying. And I'm going to keep saying it — every single day — until you believe it."
"That might take centuries."
"Then I'll say it for centuries."
Suo closed his eye.
For the first time in hundreds of years — truly the first time — he let himself believe that someone would stay.
"…Your letter," he said after a long moment. "When will you write it?"
"Tonight."
"What will it say?"
Nirei pretended to think.
"It'll say… 'Dear Suo, I love you. P.S. Please stop jumping out of windows. The guards are still talking about it.'"
Suo groaned.
"I am never living that down, am I?"
"Never."
"I hate you."
"You love me."
"…Unfortunately."
Nirei grinned and kissed his cheek.
"I'll write the letter tonight," he said. "But for now — "
He settled back against Suo's chest, right over his still-racing heart.
"— for now, just let me stay here a little longer."
Suo's arms wrapped around him.
Tighter.
Warmer.
"…Stay," he agreed.
"Always."