In a world not so different from ours, darkness lived quietly among humans—hiding, waiting, feeding. They were called demons. Creatures once human, now twisted by cursed blood, ruled by unseen leaders whose names were spoken only in fear.
Long ago, a secret organization rose to fight them—the Demon Slayers.
This is where the story begins.
The wind that night was colder than usual.
Rin Takahashi tightened his grip on the wooden bucket as he climbed the steep hill toward his home. The forest around him was silent… too silent. Even the usual chirping of insects had disappeared.
"Strange…" he muttered.
His village had always been peaceful. Hidden deep in the mountains, it was the kind of place where nothing ever happened. Rin lived there with his younger sister, Aiko, and their grandmother.
But tonight felt wrong.
As he approached his house, a sharp smell hit him.
Smoke.
Rin dropped the bucket.
"No… no, no—"
He ran.
Flames flickered against the dark sky. His house… was burning.
"Aiko! Grandma!" he shouted, rushing inside without thinking.
The door was broken. Claw marks scratched across the wood.
Inside, everything was in ruins.
And then he saw it.
A shadow moved.
Rin froze.
It wasn't human.
Its skin was pale like ash, veins dark and crawling beneath. Its eyes glowed faintly red, and its mouth… its mouth was stained with blood.
A demon.
The creature turned its head slowly toward him.
"You came back…" it whispered, its voice cracking like broken glass.
Rin's legs refused to move. Fear wrapped around him like chains.
"Stay away…" he said weakly.
The demon smiled.
"Too late."
It lunged.
But before it could reach him—
A flash of silver cut through the air.
The demon's head separated from its body in a single motion.
For a moment, everything stood still.
Then the body collapsed.
Rin stared in shock.
Standing between him and the fallen demon was a stranger.
A young man, dressed in a dark uniform, held a sword that shimmered faintly under the firelight. His expression was calm… almost cold.
"Are you hurt?" the stranger asked.
Rin shook his head, unable to speak.
The stranger glanced at the demon's body as it began to crumble into ash.
"Remember this," he said quietly. "Demons can only be killed by cutting off their heads. Anything else… won't stop them."
Rin swallowed hard.
"What… what are they?" he asked.
The man turned toward him.
"They're monsters who feed on humans," he replied. "And we are the ones who hunt them."
"Who… are you?"
There was a brief silence.
Then the man answered—
"A Demon Slayer."
Before Rin could say anything else, a faint sound came from behind him.
A weak… breathing.
"Aiko?" Rin turned quickly.
In the corner of the room, barely visible through the smoke, his sister lay on the floor.
He ran to her side.
"Aiko! Wake up!"
Her body was cold… but she was still alive.
Relief flooded his chest—
Until she opened her eyes.
They weren't the same.
A faint red glow burned within them.
"No…" Rin whispered.
The Demon Slayer stepped forward slowly, his grip tightening on his sword.
"She's been attacked," he said.
Rin looked up, panic in his voice. "She's alive! You can save her, right?!"
The man didn't answer immediately.
Instead, he raised his blade.
Rin's heart stopped.
"Wait—what are you doing?!"
The Demon Slayer's voice was steady… but heavy.
"If she turns into a demon… she will kill others."
Rin moved in front of his sister.
"No! I won't let you!"
For the first time, the Demon Slayer's expression changed.
A flicker of hesitation.
Behind Rin, Aiko let out a low, unnatural growl.
The air grew tense.
Something was about to happen.
Something that would change everything.