The sun had just begun to rise, its golden rays piercing the mist that lingered over the ruined battlefield. The shattered remains of the train smoldered around them, twisted metal and scorched wood echoing the battle's toll.
Akaza's eyes narrowed.He stood facing Tharion, arms regenerated, but for the first time in centuries—his stance wasn't eager.There was a flicker of something else in his expression. Not curiosity. Not bloodlust.
Caution.
"Who… are you?" Akaza muttered, voice low.
Tharion's gaze was calm but piercing. He held the nichirin blade at his side, forged by the Swordsmith Village Chief—a blade blessed by flame and legacy.
His reply was barely a whisper."I am the hand of the sun they fear."
With that—
He moved.
Sun Breathing – Second Form: Clear Blue Sky.Tharion spun into a flaming arc, faster than the eye could follow. The golden fire traced a halo of death that nearly cleaved Akaza's chest again.
Akaza leapt back, narrowly evading—but not unscathed.His ribs were scorched. His skin cracked and hissed.
"That breathing style…!" Akaza snarled. "That's…"
"Sun Breathing – Fifth Form: Setting Sun Transformation!"
Tharion advanced in a flickering flash, his form blurring, striking from below in a sweeping, inverted slash that lifted Akaza off the ground—severing one leg midair.
Akaza roared. The pain registered.
This isn't like the Hashira's flames. This… this is the source.
From the side, Tanjiro, Inosuke, Zenitsu, and Nezuko watched in awe, barely able to keep up.
"Who is that?" Inosuke whispered, slack-jawed.
Zenitsu, trembling, muttered, "T-That's not a Hashira. That's something else…"
Tanjiro's eyes widened, his heart pounding."That breathing… it's the same as the Hinokami Kagura. But refined. Stronger. Complete."
He looked toward Rengoku, still seated against a rock, coughing blood but alive. The Flame Hashira was staring at the battlefield, his one good eye glowing with a mixture of awe and disbelief.
"That style…" Rengoku rasped. "It's real. The legendary form… the Sun Breathing of the first swordsman."
Back in the field—
Akaza tried once more to go on the offensive. His fists shattered the ground, creating shockwaves, but Tharion weaved through them like sunlight through clouds.
Sun Breathing – Eighth Form: Solar Flame Thrust.A straight-line attack burst from Tharion's blade with such heat that it turned the air to shimmering gold. It pierced Akaza through the shoulder and pinned him into a tree.
But Tharion didn't stop.
He walked forward, each step like judgment.
Akaza regenerated—again—but with difficulty now.
"You… what are you?!" Akaza shouted, fury trembling in his voice.
Tharion didn't answer.
He simply raised his blade and whispered—
"Sun Breathing – Thirteenth Form."
And in an instant—he moved through all twelve forms in a seamless, continuous loop.Strike after strike rained down.Form after form blurred together into a divine dance of fire.
Time stopped.
Akaza saw not just the slashes—but the memories behind them.
Muzan's blood stirred.
Within the deepest part of Akaza's soul, the blood of the Demon King tried to identify this new enemy.
But it failed.
Instead—it recoiled.
It remembered something it should not have.A face.
A voice.
A world drowned in sunlight.
It saw Tharion—not as a man—but as a creature of war. A being forged in cosmic battle. A god who had faced extinction, and survived.
The blood inside Akaza screamed in ancestral terror.
Akaza stumbled back, visibly panicked now. "No… no, you're not normal. You're—You're something else!"
His regeneration slowed. His stance cracked.
And then—he turned to run.
For the first time in centuries, Upper Moon Three fled a fight.
Tharion didn't chase.He simply sheathed his katana with a whisper of steel.
The battlefield fell silent.
Tanjiro rushed to Rengoku's side, tears in his eyes. "He's alive!"
Zenitsu collapsed beside Nezuko, who clung to her brother with relief. Inosuke, for once, was speechless.
Rengoku, struggling to his feet, met Tharion's gaze.
"You… saved me."
Tharion gave him a nod. "The fire you carry—burns bright. But I wasn't about to let it die today."
There was a long pause.
Then Rengoku smiled—weakly, proudly."You fight with the spirit of the first Flame. Thank you."
Tanjiro looked up at Tharion with awe."Who are you…?"
Tharion's reply was simple.
"Just someone sent to keep the flame alive."