"Boring. Your neck isn't here, is it?"
Raiden clicked his tongue as Enmu's body regenerated once more in front of him.
That was the problem with demons. Unless their neck was severed, everything else was meaningless. Limbs, torso, even the head, none of it mattered.
For a demon of Enmu's level, those were little more than inconveniences.
Finding the real neck was the only solution.
Now that Enmu had fused himself with the Mugen Train, his neck had become part of the train itself. In the original events, Tanjiro located it through Inosuke's spatial awareness.
Raiden had no need to rely on anyone.
He sheathed his Nichirin blade, pressed his palms together, and closed his eyes.
An invisible pulse spread outward from his body, rippling silently through the entire train. Steel, wood, flesh, blood, everything registered within his perception.
It did not take long.
The scent was strongest near the carriage connected to the fuel compartment.
There.
Raiden opened his eyes.
Without hesitation, he moved.
Enmu had not completed his fusion yet, meaning the position of his neck was still fixed. If the fusion finished, the location could shift at will.
Raiden would not give him that chance.
Seeing his movement, Enmu's composure cracked.
This boy could ignore his Blood Demon Art, knew about his integration with the train, and was now heading directly toward the critical point.
How?
Aside from Muzan, who could read thoughts, no one should have known about this plan.
"Bang, bang, bang!"
Dozens of purplish red torsos burst through the roof of the train, blocking Raiden's path. Eyes opened across the grotesque flesh, each marked with the kanji for dream.
Every possible angle was covered.
Enmu still refused to believe his Blood Demon Art had failed.
Steel flashed.
A torso split cleanly in half.
This time, Enmu understood why.
And because he understood, fear settled into his bones.
Raiden was killing himself inside the dream.
The instant hypnosis took hold, Raiden's body reacted without hesitation. He would draw his blade and sever his own neck within the illusion, breaking free immediately.
The first time could have been instinct.
But every time afterward, the movement became smoother, faster, almost reflexive.
Even when Enmu's gaze brushed him now, Raiden's body showed no pause at all.
He had adapted.
He had mastered dying.
Enmu felt exposed, as if this white haired swordsman had peeled apart every layer of his being.
Raiden was getting closer.
Panic took over.
Countless strips of purple flesh erupted from the train, surging toward Raiden like a tidal wave.
His speed slowed under the relentless assault, yet Enmu's expression only worsened.
Overusing his abilities would delay his full integration with the train. But if he held back, Raiden would reach his neck.
"Sleep!"
Enmu's severed hand rose from the carriage, the mouth on its palm opening wide.
This time, uninterrupted, the Blood Demon Art activated perfectly. Under layered hypnosis, Raiden remained still for a fraction longer.
Enmu's eyes widened in anticipation.
Then Raiden moved again.
"I'm almost there," Raiden said calmly. "I'm done playing."
He felt it beneath his feet, the steel frame of the fuel carriage, saturated with demonic presence.
He planted himself firmly.
Purple black flesh converged from every direction.
Lightning flickered across Raiden's eyes.
A sharp electric crackle filled the air.
Arcs of gold began dancing around his body, wrapping his blade in radiant light.
For a heartbeat, everything froze.
Then he vanished.
Tiny flashes of gold pierced through the converging mass of flesh. Raiden surged forward, body low, blade drawn tight against his side.
"Thunder Breathing, First Form, Thunderclap and Flash."
The words came as his body exploded into motion.
He became a streak of lightning cutting through the storm. Flesh, eyes, tendrils, all split apart before they could even register his presence.
His speed was absolute.
The writhing flesh never touched his clothes.
Within the chaos of darkness and shifting meat, Raiden reached the fuel carriage connection.
His blade, blazing with golden lightning, struck directly at Enmu's true neck.
At the last instant, the train convulsed.
Thick masses of purplish black flesh erupted from the steel, forming a hardened barrier over the critical point. The surface gleamed with an oily membrane, writhing and expanding as if alive.
The moment Raiden's blade met the defense, the flesh swelled, attempting to engulf the sword and trap it.
His expression did not change.
The lightning around him intensified.
"Thunder Breathing, Third Form, Swarm of Hornets."
His voice was low, steady.
The lightning shifted.
Instead of a single overwhelming strike, countless fine arcs burst outward, thin and precise. Each bolt pierced the flesh like a needle, invading its structure and tearing it apart from within.
The hardened membrane began to crack.
The oily sheen dimmed.
The writhing mass faltered under the relentless assault of concentrated electricity.
Enmu felt it.
His final defense was collapsing.
Impossible.
The barrier he had constructed at the last moment, reinforced by his merging body, was being dismantled by a human.
The cracks spread.
With a sharp metallic ring, the flesh barrier shattered completely.
Raiden's blade cut cleanly through Enmu's neck.
Lightning surged along the steel, flooding into the core of Enmu's existence and tearing apart his life force from the inside.
For a suspended instant, silence blanketed the night.
Then Enmu screamed.
His body, fused with the Mugen Train, began to disintegrate. Purple black flesh peeled away from steel, dissolving into ash as golden arcs flickered and faded.
Raiden stood steady atop the train, white hair whipping in the wind, blade lowered at his side.
The nightmare had ended.