Demon Slayer: Seraph of Radiance

Kawanishi was a little surprised—he hadn't expected Sayuki to have those kinds of feelings for him.

But truly, he had only ever seen Sayuki as a little sister, nothing more.

Spitting out the now unbearably bitter bamboo leaf from his mouth, he spoke seriously:

"Sayuki, you should know that I've always treated you like a younger sister."

"You deserve someone better, someone who can give you a better life. That person isn't me. In your life, I can only ever be a big brother you can rely on."

"So go to Asakusa. I'm sure there's someone waiting for you there."

Sayuki had anticipated this answer, but her face still fell. Tears welled up in her eyes.

She fought to hold them back and, without a word, turned and ran down the mountain.

"Kawanishi-nii, I hate you! I don't ever want to see you again!"

"Sayuki..."

Kawanishi followed at a distance, worried she might stumble. When she finally reached home, he gently knocked on her door, but Sayuki didn't respond.

Still, he could hear her muffled sobs from inside.

He felt guilt and self-reproach—but no regret.

He believed he couldn't let Sayuki stay. Besides, young hearts are fickle; one day, Sayuki would meet someone new.

Kawanishi convinced himself that Sayuki couldn't distinguish between familial affection and romantic love.

Maybe it was the absence of her parents that made her misinterpret her feelings for him...

"Sayuki, if you ever come back, let me know. I'll come see you."

"You'll understand one day, I promise."

He waited for a long time but received no answer. As the sky darkened and night fell, Kawanishi quietly left.

When he returned the next day, the house was already empty. Every time he passed by since, he would still stop to check—but Sayuki never returned.

"Sayuki, are you home?"

Kawanishi's hand froze mid-knock. The door creaked open.

There she was.

She'd grown quite a bit—now standing nearly 170 cm tall. Her slender figure was graceful, her complexion still as delicate and fair as ever.

When she saw Kawanishi, her eyes lit up into crescent moons—a look he was all too familiar with.

She wore a short-sleeved kimono embroidered with countless pink cherry blossoms. Her long golden hair, flowing like a shimmering waterfall, was just as mesmerizing as before.

"Kawanishi-nii... I finally get to see you again..."

Overjoyed, Sayuki threw herself into his arms.

He stood frozen as she embraced him, her cheek pressed against his chest.

Sayuki… what have you been through… If I hadn't let you go to Asakusa, could this have been avoided...?

Sadness flickered in his eyes. Every time Kawanishi thought fate had been cruel enough, it would mock him and show him it was only just beginning.

He hugged her back, hiding his sorrow beneath a joyful smile.

"I missed you too, Sayuki."

"You must've had such a great time in Asakusa, huh? You even forgot about your cheap big brother here."

Sayuki rubbed her cheek against his chest, unwilling to let go, as though savoring this warmth:

"No, I missed home as soon as I got there. But my father... I don't know why, no matter how I begged, he wouldn't let me come back. He even had people watch me constantly."

"It was only recently that I managed to sneak out and find you."

"I really, really missed you..."

After three minutes of hugging, Kawanishi finally spoke helplessly:

"Sayuki, have you hugged enough yet?"

She released him, then teased:

"Are you shy? I haven't hugged you enough—never enough."

Kawanishi gently ran his hand through her golden hair, a conflicted look flashing in his eyes.

"Kawanishi-nii, let's go inside. It's cold out here."

He glanced into the house behind her—the windows were tightly shut, not a sliver of light getting through. Though it was daytime, the cloudy sky left everything dim.

Inside, however, the bright electric lamps filled the room with warm light.

Electric lamps… In this world, Kawanishi had only ever seen them in Sayuki's house. Everyone else used oil lamps.

Simple wires and glass powered by electricity—yet capable of driving away darkness with light and heat. A miracle of nature and man.

Perhaps the existence of demons was another miracle—or a calamity—of this world.

Sayuki held tightly onto Kawanishi's hand, as if afraid he might disappear.

Once inside, they sat side by side on soft tatami mats. Sayuki gently leaned her head against his shoulder.

Kawanishi didn't pull away, but his inner turmoil remained unresolved.

Then Sayuki, as if suddenly remembering something, looked at him with concern:

"Kawanishi-nii, what happened to your family?"

"I came looking for you once, but I only found their graves..."

"I thought something had happened to you too... but thank goodness you're alright."

It had been some time since that tragedy, but Kawanishi could still feel his family's spirits watching over him, clearly and vividly.

The help from Tanjuro, the guidance from Kie—they weren't illusions; they were real.

They hadn't completely passed on. They were with him in a new way.

It wasn't how he would've wanted it, but it offered him some comfort. He never felt truly alone or powerless.

There was still light in his life. No matter how cruel fate became, Kawanishi wouldn't be lost to darkness.

Without sadness in his voice, he calmly said:

"My family was attacked by demons. Only I survived. Tanjiro wasn't home at the time, so he should still be alive too."

"In my fear, I ran away. Their bodies were likely buried by Tanjiro… I hope he's okay."

His gaze hardened as he spoke, the bloodlust from slaying countless demons seeping from his body:

"Sayuki, you know what demons are, right?"

The killing intent wasn't overwhelming but was sharp and intense—anyone who had experienced bloodshed would sense it instantly.

Yet Sayuki seemed completely unaffected. She only tightened her collar, snuggling closer to him as if the air had suddenly grown cold.

She looked both frightened and curious:

"Demons? My father used to scare me when I was little, saying demons would eat me if I misbehaved..."

"Are you saying demons really exist?"

Kawanishi watched her carefully—her curiosity and fear were genuine, written plainly across her face.

Could I have been wrong?

He withdrew his killing intent, and the room's atmosphere softened once more.

"Yes. Demons appear at night and feed on humans. You should never go out after dark, Sayuki. Even if ordinary people rarely encounter them, it's always better to be careful."

Hearing the warmth in his voice, Sayuki's lips curved into a bright, joyful smile.

Her brows arched like a crescent moon in the sky.

(End of Chapter)