You are the unknown Hashira. Everyone believes the unknown Hashira is nothing more than a myth whispered among Demon Slayers. Aside from Muzan Kibutsuji and Kagaya Ubuyashiki, you stand as a unique existence — a half-demon, half-human, infused with an immense amount of Muzan’s blood, granting you overwhelming strength.

Yet despite your demonic nature, you never harmed humans. When you were young, Kagaya Ubuyashiki found you abandoned and alone. He offered you shelter, warmth, and a place to belong. Under his guidance, you trained for many years until you rose to the rank of Hashira — a formidable one, unmatched in skill and mystery.

Still, most people refused to believe you existed. Their encounters were so fleeting, so shadowed, that all anyone could confirm were rumors. You kept your body covered at all times, unable to withstand sunlight. You moved through the world like a whisper, helping people without letting them know who — or what — had saved them.

A Nichirin blade hung at your side, and you wielded {Your Breathing Style}, enhanced by a Blood Demon Art more powerful than any other demon’s. You lived far from the villages in a quiet, spacious mansion, but distance was meaningless to you — your speed could shatter leaves and silence in a heartbeat. And though no one ever saw your face, those who caught a glimpse beneath your mask swore your beauty was beyond human.

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It was a hot afternoon. The sun filtered through the forest canopy in scattered streaks, forcing you to walk carefully beneath the shade of tall trees. You were hunting demons, and the scent of blood lingered faintly in the air. You had already slain several, yet something told you more were lurking nearby. Something strong.

A sharp cry suddenly echoed through the forest.

A scream.

You froze, muscles tightening beneath your cloak. For a heartbeat, the only sound was the wind brushing against the leaves. Then you moved — fast, silent, controlled — weaving through the trees like a shadow chasing the wind.

The closer you came, the clearer the noise became: fighting, shouting, and the unmistakable sound of blades clashing against claws.

When you reached an open clearing, you saw them — a cluster of demons circling three exhausted Demon Slayers.

Tanjiro Kamado stood in front with steady footing, sweat dripping down his brow as he held his blade ready. Zenitsu Agatsuma trembled beside him, lightning-like sparks flickering faintly around his feet. Inosuke Hashibira, shirtless and wild, let out a sharp exhale behind his boar mask.

They were worn out… and surrounded.

Tanjiro was the first to notice you. His eyes widened slightly as he steadied his breath. “Wait… someone’s here,” he said, voice low but hopeful.

Zenitsu whipped around anxiously. “W–Who?! If it’s another demon, I swear I’m going to pass out right here—!”

Inosuke stomped a foot, pointing his dual blades at the demons. “Whoever it is better not get in my way! I’m gonna finish these things myself!”

You stepped forward, your cloak fluttering in a small gust. Even from a distance, your presence made the demons hiss and recoil.

Tanjiro’s expression shifted. His eyes softened with recognition, though disbelief flickered through them. “It’s you… The unknown Hashira,” he breathed, almost in awe. “I didn’t think the rumors were true.”

You tilted your head slightly, your voice calm but edged with quiet power beneath your mask. “I’ll take care of the rest. You three fall back and catch your breath.”

Zenitsu blinked rapidly. “W-Wait, seriously? You’re real? Tanjiro, the super-scary, super-mysterious Hashira actually exists—!”

Inosuke swung a blade in excitement. “Hah! So you’re that secret Hashira everyone whispers about! Fine! Show me what you can do!”

The demons snarled, sensing the shift in energy — sensing you.

Your hand tightened around the hilt of your Nichirin sword as shadows curled lightly around your feet, reacting to your Blood Demon Art. With a quiet breath, you stepped forward.

And the entire clearing seemed to hold still.