Chapter Text
Tomioka Giyu is turning 19 years old when he met the Kamados.
The air on the mountain was thin, biting, and perfect. Giyu preferred the cold. It numbed the constant, sharp ache in his chest a localized pressure he had lived with for so long it had become a second skin.
He runs as his crow Kanzaburo guides him at the snowy mountain for his next mission.
“Caw, caw…. Demon sighting ahead! North-east!” “A demon sighting nearby. Caw… caw”
The scent of blood broke his daydreaming. It was thick, metallic, and fresh. Giyu moved. “Run fast…. Don’t be late… please let me protect people”
He arrived in a clearing of crimson snow to find a boy clutching a snarling girl.
“I am late again…. Another family, he thought distantly. Another home turned grave because I am not fast enough”
Giyu attacked the demon girl but the human boy shielded the demon.
Giyuu stepped forward, water-breath steady in his veins, steel arcing toward her neck in a flawless execution
And stopped.
The boy had thrown himself between them.
The edge of Giyuu’s nichirin blade hovered inches from the boy’s neck.
His eyes darkened.
“Why do you protect it?” His voice came out controlled. Even. Practiced.
The boy trembled violently, yet did not move aside.
“She’s my sister!” he cried. “Please! She hasn’t eaten anyone! She’s not like other demons!”
Not like other demons.
Giyuu’s jaw tightened.
They all say that. He had heard variations of those words before. Humans clinging to impossible hope. Refusing to accept what was already lost.
“You call that thing your sister?, Move” he ordered.
Instead, the boy dropped to his knees and bowed, forehead pressing into bloodstained snow.
“Please! I’m begging you!”
The sight hit something old and jagged inside him.
Begging….. Groveling….. Crying for mercy from something merciless….
A flash of memory: blood soaking into tatami mats. A sister’s body. Helplessness swallowing him whole. It was the same helplessness he had felt years ago, watching the people he loved bleed out while he stood by, safe and fragile.
"Don't give others the chance to kill you!" Giyu roared. The force of the shout strained his throat, a sharp reminder of the physical cost of his facade. "Don't grovel! If that were effective, your family wouldn't be dead!"
He watched the boy’s desperation turn into a desperate.
The boy flinched.
Good, Giyuu thought harshly. Let it hurt. Pain teaches faster than kindness.
But instead of retreating, the boy grabbed his fallen axe and charged.
The attack was clumsy. Untrained. Driven entirely by emotion.
Giyuu sidestepped and struck the boy’s wrist, disarming him effortlessly. The axe disappeared into the snow.
Weak….. Too weak to survive like this. But he is determined. Maybe they are different…
Behind him, the demon girl had stopped struggling.
She stepped forward.
Not toward Giyuu.
Toward her brother.
Shielding him.
Giyuu froze.
Demons protected themselves. Not others.
Freshly turned demons were the worst of them, ruled entirely by hunger.
Yet this girl, trembling, teeth bared behind bloodstained lips, placed herself between danger and her human brother.
Why?
The wind shifted, pressing fabric against his torso. Beneath the tight bindings wrapped around his chest, sweat gathered despite the cold. The layers felt suffocating for a fleeting second.
Weakness invites doubt. Doubt invites delay. Delay invites death.
That had been his rule.
He stepped forward and struck the demon girl with the hilt of his sword, precise and controlled. She collapsed into the snow, unconscious.
He knelt beside her. Up close, she looked impossibly young.
He runs to find a length of bamboo and secured it carefully between her teeth. He wiped the blood from her face with a clothe and took the clothes to cover her small body.
The boy is knockout.
So Giyuu waited.
Snow fell in quiet spirals around them. Kanzaburo perched on a branch above, silent now, watching.
What are you doing? Giyuu asked himself.
He was breaking protocol.
He was risking everything on instinct.
When the boy finally stirred, panic flooded his expression before settling into confusion.
“You…” he whispered.
Giyuu stood, retrieving his blade.
“Go to Mt. Sagiri,” he said. His voice had returned to its distant monotone, safely stripped of emotion. “Seek out Sakonji Urokodaki. Tell him you were sent by Tomioka Giyuu.”
The boy blinked.
“My name is Kamado Tanjiro,” he said, bowing deeply despite trembling limbs. “Thank you. Thank you so much, Tomioka-san. I promise you… I will find a cure. I will get strong. I will avenge my family.”
Promises.
Giyuu remembered making one once.
It had not saved anyone.
“Do not expose her to sunlight,” he said quietly.
Tanjiro nodded fiercely, tears falling freely into the snow.
Giyuu turned away.
The forest swallowed him in moments.
As he moved, a bead of sweat slid down his spine, trapped beneath binding and cloth. The weight of concealment pressed heavier than his sword at his hip.
He had spared a demon.
He had trusted a stranger.
He had acted not as a member of corps bound by law
But as someone who still believed change was possible.
That was dangerous.
Yet as the mountain wind followed him into the trees, something long dormant stirred beneath layers of discipline and disguise.
Hope…..
And for the first time in years, Tomioka Giyuu allowed himself to feel it.
Kanzaburo guides him to his next mission. He prays his decision is right, he still can’t shake the feeling that he betrayed the corps for strangers.
“Caw!!! Next mission! West ridge! Demon confirmed!”
Giyuu exhaled slowly.
“Yes,” he murmured.
The crow dipped lower, guiding him through the forest canopy. Giyuu followed without question. That was simpler. A crow’s direction did not waver. Orders did not hesitate.
Demons did not deserve mercy. Humans did not deserve false hope.
His steps were steady, but his mind was not.
What have I done? The question lingered like frostbite beneath the skin.
He had spared a demon. He had chosen compassion over protocol. His jaw tightened. The girl had not attacked a human. She had protected one. It was an anomaly. And anomalies deserved examination.
The justification sounded hollow even inside his own head.
You broke the rules.
The Corps was built on absolutes. Demons kill. Slayers kill demons. That symmetry was what kept humanity alive.
He had introduced uncertainty into that equation. He leapt over a fallen trunk, landing soundlessly in fresh snow.
If she kills someone… it will be your fault. His chest constricted.
“Demon!” the crow cried. “Below! Smell of decay!”
The scent hit him a second later. Rotten flesh and fear.
Another demon.
Giyuu’s thoughts snapped into alignment. Good. A demon did not question him. A demon did not complicate him.
Steel slid free from its sheath.
The creature emerged from the underbrush, elongated limbs dragging across the snow, mouth splitting too wide in a grin of jagged teeth.
“Hashira…” it hissed.
Giyuu did not respond.
Water Breathing. His stance lowered. Breath deepened. The world narrowed to rhythm.
First Form: Water Surface Slash.
The blade moved like a ripple across still water.
The demon’s head separated cleanly from its body. It barely had time to scream. Snow resumed its soft descent. Giyuu stood motionless as the demon disintegrated into ash.
This is what you are meant to do. His grip on the sword remained firm long after the threat vanished. He stared at the fading remains.
The earlier scene replayed uninvited. The boy’s eyes. The demon girl’s protective stance. The way hope had flickered where hunger should have ruled.
He closed his eyes briefly.
Please let this not be a mistake. The prayer surprised him. He was not a man who prayed. But the words formed anyway, quiet and desperate beneath the mask of composure.
Let my decision not cost innocent lives. Let me not have betrayed the Corps. The wind shifted through the trees.
Kanzaburo hopped down to a lower branch, watching him.
Giyuu moved to the base of a tree and knelt. From within his uniform, he withdrew paper and ink, protected carefully from moisture.
His handwriting was precise. Controlled. Each stroke measured.
Urokodaki-sensei,
I encountered a demon unlike any I have seen. Recently turned. Yet it did not attack a human. It shielded one her brother. I chose not to execute it. I have directed the siblings to Mt. Sagiri. The boy’s name is Kamado Tanjiro. I ask that you observe them personally.
If the demon proves hostile, you may deal with it as you see fit. If it does not… I believe it warrants further consideration.
The boy, Kamado Tanjiro wants to be a slayer to find a cure. I believe they will bring difference soon. Something in him makes me believe in him.
I accept full responsibility for this decision.
Tomioka Giyuu
He stared at the final line. He folded the letter carefully and secured it.
Kanzaburo fluttered down, landing before him.
“You send?” the crow asked.
“Yes,” Giyuu said quietly.
He tied the letter securely to Kanzaburo’s leg.
“Deliver this to Urokodaki-sensei.” The crow took flight without hesitation.
Giyuu watched him disappear into the pale sky.
He felt fragile….. Not because he had spared a demon… But because for the first time in years, he had acted not out of duty…
But out of belief…. And belief was far more dangerous than any blade.