The abandoned district lay silent, swallowed by fog that clung to the shattered roads and half–collapsed buildings. Each step echoed like a memory of a city that once breathed. Tanjiro and Giyu moved in cautious silence, their senses stretched thin. The scent in the air was thick. Heavy. Wrong.
Tanjiro stopped first.
"…Giyu. The smell changed."
The former Water Hashira narrowed his eyes. "He's close."
The pavement ahead cracked. A low tremor shivered through the ground before a square block of flesh punched upward, rising like a tower. It was shaped like a perfect cube, but its surface pulsed, veins glowing faintly with a red-orange light.
A voice followed.
"Oh, good. You made it… I was getting bored."
From atop the cube stepped a demon with metallic skin that looked hammered and smoothed by a blacksmith's patient hand. His arms were long, ending in heavy fists. His eyes gleamed a sick yellow.
"I am Vally. Upper Four's apprentice." He smiled, revealing teeth shaped like iron nails. "Let's play."
Giyu slid his hand to his sword. "Be ready."
Tanjiro answered with a nod, but Vally moved first.
Two cubes tore themselves from his torso and shot at them like cannonballs. Tanjiro flashed forward, slicing one in a clean arc, but the metal-like flesh resisted. His blade embedded halfway.
Thick… too thick. He hardened it beyond a demon's normal flesh.
Giyu met the second cube with a clean, fluid strike.
Water Breathing — Tenth Form — Constant Flux.
The cube split neatly, the two pieces smashing into the ruined buildings behind.
Vally grinned.
"Interesting. You two cut well. Let's see if you can handle… this."
He raised his arm.
It dropped.
Instantly, the air seemed to double in weight. The ground groaned. Tanjiro felt his knees bend.
"Weight… increasing…!" He clenched his teeth as his body tried to fold under invisible pressure.
Giyu stayed firm, though even his stance shifted slightly.
"Tanjiro. Move. He's testing his range."
"I know…! I'll break through!"
Tanjiro focused, gathering Reiryoku into his legs.
Blue sparks danced around him.
He leaped.
Vally laughed. "Good! Then catch!"
A massive cube formed above Tanjiro, easily ten times larger than the previous ones. It descended with the weight of a meteor. Tanjiro thrust his hands upward and released an eruption of spiritual pressure.
The cube stopped.
Barely.
The shockwave of the impact blew dust in every direction.
Tanjiro strained. His muscles trembled.
He's not just adding weight to the cube. He's adjusting the force pulling it downward. Gravity manipulation? No… it's his blood manipulation technique.
"Kid," Vally called, "holding that up is cute, but…"
Electricity crackled across his arms. Lightning arced across the cube.
"…can your nerves handle this?"
It hit Tanjiro like a spear to the spine.
His muscles locked instantly.
He froze in place, teeth gritting so hard they nearly cracked.
"A-ah—!"
His arms trembled violently, the cube threatening to crush him.
"Tanjiro!" Giyu dashed forward, blade flashing.
Another cube shot from Vally's side, spinning like a buzz saw. Giyu dodged sideways, then another cube slammed down in front of him, forcing him away from Tanjiro.
"You won't reach him," Vally taunted. "Let the kid break."
Giyu's eyes sharpened.
"Not happening."
He vanished.
Water Breathing — Seventh Form — Drop Ripple Thrust.
A pinpoint thrust toward Vally's throat.
But Vally hardened his neck instantly, metal-like skin stopping the blade cold.
"Too slow."
His fist crashed downward.
Giyu blocked, sliding back several meters, boots carving lines into the stone.
But he didn't fall.
Vally laughed. "You're durable for a Hashira. But that kid's going to be crushed."
Giyu flicked blood from his blade.
"You talk too much."
He inhaled once.
Then he moved with a speed that cracked the street beneath his feet.
Dead Calm.
A level of stillness that cut through chaos.
Giyu's body blurred, slipping between falling cubes, dodging electric bursts, reading the pattern. Every move Vally made required shifting mass within his body before creating a cube. A faint vibration in his muscles telegraphed the shape and direction.
Giyu struck.
Slice.
Slice.
Slice.
Pieces of Vally's flesh scattered, regenerating quickly… but not instantly.
Enough time.
"Tanjiro! Move now!"
Tanjiro clenched his frozen muscles. Not yet… not yet… breathe… concentrate…
Blue aura erupted around him.
He forced his legs to bend.
Then he exploded upward, pushing the cube aside just enough to slip free before it crashed into the earth like a thunderclap.
Tanjiro rolled in midair and landed beside Giyu, panting lightly.
"You good?" Giyu asked without looking back.
Tanjiro gave a shaky smile. "Thanks. Yeah. Barely."
Vally tilted his neck. "Cute teamwork. Now let's end it."
He lifted both arms.
Countless cubes formed around him like floating satellites. Lightning webbed across them. Each cube grew heavier, denser, vibrating from contained force.
"This will flatten the whole district."
Tanjiro's eyes widened.
Then he slowed his breath. Inhaled.
Exhaled.
"I'll aim for his joints. Giyu… take his core."
Giyu nodded.
Vally launched the cubes.
They fell like meteors.
Tanjiro dashed forward, weaving between impacts. Each cube that hit the ground created craters, sending debris and shockwaves through the air.
One cube plummeted toward him from above.
Tanjiro swung.
Water and flame spiraled together.
Hinokami Kagura — Clear Blue Slash.
The cube split perfectly.
Giyu slipped beneath the chaos, his calm expression never faltering. His blade danced through falling pieces of flesh, avoiding lightning bursts with impossible precision.
He reached Vally.
Vally grinned. "Right where I want—"
But Giyu was already swinging.
Water Breathing — Eleventh Form — Dead Calm.
Silence swallowed everything.
All sound vanished.
Each of Vally's attacks dissolved into thin threads of water-like cuts. Every cube disintegrated. Lightning fizzled out. Even Vally's shout cut short.
Giyu's blade reached his chest.
A single slash.
So clean it looked like nothing happened at all.
Then Vally's upper body slid off the lower.
He fell with a metallic thud.
Tanjiro landed near Giyu, expression firm.
"…That was incredible."
Giyu sighed. "I told you. I still remember how to kill demons."
Vally's head rolled, mouth still trying to speak as it turned to ash.
"Demonic… world… was… better…"
Giyu sheathed his sword.
"No. It never was."
The last embers of Vally's remains scattered in the wind.
Tanjiro looked ahead into the fog-covered ruins.
"One more demon gone."
Giyu nodded. "We keep moving. Muzan's influence won't weaken on its own."
Tanjiro straightened his back.
"Then let's make sure the next one falls even faster."
Together, they stepped deeper into the forgotten city, where the next nightmare waited in the dark below.