Meanwhile...
After their appointment as Hashiras, Tanjiro, Inouske and Zenitsu had become quite busy. Although no one among the existing Hashiras openly said anything, the group of three felt it.
They needed to work hard and gain respect of the Hashiras. At least Zenitsu and Inouske had to. Tanjiro already earned quite some respect from them.
So that fateful night, they were on their usual patrol when Inouske's crow suddenly swooped down.
"Caw! Caw! A strong demon has appeared in the village nearby. Hashiras are to move immediately."
Tanjiro's brows furrowed. "It has to be a Lower Moon. Let's go."
Unlike him, Inouske's thoughts were simple. "Muhahaha! Inouske-sama is going for the kill. Come, come, demons!"
While the two rushed ahead, Zenitsu trailed behind them reluctantly, his thoughts practically visible.
'What's this? We've just become Hashiras and we're going after another demon already?! Can't I just retire?!'
Despite his discouraging thoughts, he still followed them and arrived at the village.
Unexpectedly, what met them at the gate was a porcelain flower vase.
Although it looked perfectly mundane, Tanjiro's nose and Zenitsu's ears weren't deceived.
"Eeeeekkkk! It's a demon!!!"
Zenitsu shrieked, clinging to Tanjiro like a startled damsel.
Unfortunately, now wasn't the time to scold him.
Tanjiro's expression was grim. After hearing bits and pieces from the existing Hashiras, he knew this demon—barely.
Although he wasn't aware of the changed rankings, he knew that demon was an Upper Moon.
He clenched the hilt of his sword, preparing to attack.
Inouske beat him to it.
"Heee-aaaH!"
Shouting like a western cowboy, he lunged at the vase and swung his chipped blades.
The vase shattered, then reappeared a distance away.
Tanjiro quickly sensed something amiss.
From the new vase, a terrifying figure appeared. Terrifying not in the sense of power, but in appearance. It was like something out of a horror movie.
With six little arms from his shoulders, Gyokko clapped happily.
"Uwaahh! This is so amazing!"
His left mouth grinned.
"Meeting three beautiful children, good art resources, aren't you?"
Inouske didn't care about his bullshit though.
Instead, he charged at the demon with a grin hidden under his boar mask.
"Y-you can't just rush in like that!" Zenitsu screeched, his hands trembling as electricity flickered faintly along his blade. "These things aren't normal! Their movements… they're faster than demons we've fought before!"
"Shut up, yellow crybaby!" Inosuke bellowed, spinning through the swarm like a wild beast. "Leave the strategy to me!"
Everyone else doubted he had a strategy, though.
Tanjiro didn't reply. His breath came steady, his hands gripping his sword tightly. Gyokko's presence was suffocating, his blood demon art overwhelming the cave with endless monstrosities. But what made Tanjiro's skin crawl wasn't just the demons. It was the way Gyokko admired their suffering.
He looked at them like unfinished sculptures.
It didn't matter.
"Water Breathing… Fourth Form: Striking Tide!"
Tanjiro's blade swept in a whirlpool of strikes, slicing through a wave of grotesque fish monsters. Their bodies collapsed, twitching, only for more to crawl out of Gyokko's pots.
"Exquisite!" Gyokko squealed, his bulbous eyes rolling. "The more you struggle, the more beautiful your deaths will be!"
A massive pot emerged behind him. From its mouth spilled a serpent-like creature with rows of human arms instead of fins. Its maw gaped wide and lunged at Tanjiro.
"Breath of the Beast… Second Fang: Slice 'n' Dice!"
Inosuke leapt overhead, carving the serpent into bloody chunks before it reached Tanjiro. "Hah! You think you can swallow the great me?! I'll eat you, fish-face!"
Gyokko's laughter echoed, shrill and piercing. "Yes! Yes! Keep fighting! Your desperation adds to the artistry!"
Zenitsu shook, knees buckling. But for a moment, his golden eyes narrowed. His breathing steadied—not the erratic whimpers of fear, but the rhythm he'd drilled into his soul. Lightning crackled faintly.
"…You two… don't drop your guard." His voice was calm, firm, so different that even Tanjiro glanced back at him.
Zenitsu's hands no longer trembled. He was serious.
The battle worsened as Gyokko himself entered the fray, his body slipping in and out of pots at blinding speed. He emerged behind Tanjiro, claws lashing like curved blades.
"Water Breathing—Seventh Form: Drop Ripple Thrust!"
Tanjiro turned, thrusting forward. His blade grazed Gyokko's arm, but not enough to cut it. The Upper Moon danced back into another pot with a grotesque giggle.
"Too slow! Too weak! You can't hope to scar my perfect body!"
Tanjiro panted, sweat dripping down his temple. His chest ached, his body screaming from the intensity. His heart raced wildly—faster than it ever had before. Heat flushed through him, his blood boiling.
No… not now…
Images flashed before him: Nezuko smiling, his comrades fighting at his side, the lives depending on him. His spirit burned hotter than his body could endure.
I can't lose here. I have to protect them.
The air rippled. His pulse thundered. And then—
A mark, dark and flame-like, burned across Tanjiro's forehead.
A surge of heat spread through his body, yet it didn't weaken him—it sharpened everything. His muscles thrummed with energy, his vision clear, movements faster, sharper.
Zenitsu's eyes widened. "Tanjiro…! Your head…!"
Inosuke roared, "What the hell is that?! Did you change your scar?!"
Tanjiro's breathing deepened into the familiar rhythm of Sun Breathing. His blade ignited with fiery light.
"Hiiiii…" He inhaled deeply, every muscle aligned with his breath. "Sun Breathing: Flame Dance!"
The forest outside the village lit with streaks of fire as he lunged forward, slicing apart Gyokko's summons in a blazing arc.
Gyokko shrieked, retreating into his pots. "Wh-what is this?! That speed! That power! You weren't this beautiful before!"
As Tanjiro pressed forward, Gyokko unleashed his true art. His body twisted, transforming into a grotesque humanoid-fish hybrid with golden scales and sharpened claws. The air grew heavy with killing intent.
"Marvel at my ultimate form!" Gyokko screeched, expression full of self praise. "A masterpiece that transcends life itself!"
He slashed, his claws shattering stone. Inosuke barely dodged the attack, cursing. Tanjiro deflected, sparks flying as steel met claw.
Zenitsu inhaled, electricity sparking violently around him. His hair lifted with the static. His eyes opened fully—sharp, unclouded.
"…If I don't fight now… Tanjiro and Inosuke will die."
He lowered into stance. His breathing was slow, steady. His voice, calm.
"Thunder Breathing… First Form."
Lightning erupted as he vanished from sight. The forest illuminated in a blinding flash as Zenitsu struck Gyokko's side. Blood splattered as four limbs were cut, the Upper Moon stumbling.
"You…!" Gyokko howled.
But Zenitsu had already moved again, faster, sharper than ever. "Thunderclap and Flash… Sixfold!"
The cavern quaked under the storm of lightning. Gyokko screeched, scales tearing from his body as Zenitsu's blade ripped through him in streaks of thunder.
"Now, Tanjiro!" Zenitsu roared.
Tanjiro's mark pulsed, heat burning through his veins. He surged forward, breath synchronized with his heartbeat. A form he hadn't learnt was suddenly imprinted into his mind.
"Sun Breathing… Twelfth Form: Flame-Wheel!"
He spun in a fiery cyclone, his blade carving straight into Gyokko's torso. Inosuke followed immediately, leaping with a roar.
"Beast Breathing… Fang Three: Devour!"
His dual swords hacked into Gyokko from the opposite side, tearing through scales and flesh.
"NOOOO! My beautiful form! My—my masterpiece—!"
The three Slayers struck as one. Flame, lightning, and beastly fury tore Gyokko apart. His body convulsed, splitting into fragments before crumbling into ash.
The battlefield fell silent. Only their ragged breathing filled the darkness.