The golden glow of paper lanterns guided Klaus and Sofie through the winding stone halls of Ashina Castle once more.
Lady Tatsuki was already waiting by the entrance, arms crossed, hair swept behind her in an elegant braid, and a wild gleam in her eyes.
"There you two are," she grinned. "We're going to have a lot of fun tonight."
Klaus raised an eyebrow. "Wait… weren't we just summoned for dinner?"
Tatsuki nodded. "Yup."
"Then why are we headed toward the gates?"
"Oh," she said casually, "because I wanna show y'all the wonderful nightlife and culture of Japonica."
The trio reached the towering gates. The general from before bowed deeply and said nothing as he pulled them open.
Beyond—
A wave of warm light and laughter surged into the night air.
Japonica's Night Festival.
The street exploded with color. Rows of glowing stalls stretched endlessly into the distance beneath a velvet sky dotted with stars. Crimson lanterns lined the walkways, casting amber hues across the bustling crowd. Paper signs danced in the wind, advertising roasted squid, yakitori, ramen, ice-cold ramune, takoyaki, and sweet mochi balls.
People swayed to festival music. Children laughed, couples strolled hand in hand, and vendors shouted joyfully over sizzling grills.
Sofie's eyes sparkled.
"Wooooowww…"
She immediately ran to the nearest food stall and shoved a skewer into her mouth.
"Mnnfhh—s'good!" she mumbled, still chewing.
Klaus blinked, following more slowly. "How is your mouth never full enough to stop talking?"
They moved together through the glowing streets. Sofie played a mini ring toss and nearly knocked over the vendor's prizes. Klaus tried a bottle of sour melon ramune and accidentally drank it with the marble still inside. Tatsuki laughed the entire time, clearly in her element.
After hours of food, games, and chaotic charm, the trio stepped away from the glowing city gates.
Klaus finally asked, "Alright… where to now?"
Tatsuki smirked. "You'll see."
They ventured into the outskirts, where lanterns faded and silence fell.
A long, narrow path led them through shadowed woods until a single building appeared — old, quiet, and mysterious.
A crimson door stood at its center.
Tatsuki stepped forward and knocked three times.
BANG. BANG. BANG.
From the other side, a voice crackled through an old speaker. "Password?"
Tatsuki leaned in. "The blade glows brighter when drowned in sin."
Click.
The door creaked open.
They descended stairs, deeper and deeper beneath the earth.
Finally, they stepped into an elevator. The walls trembled as it descended further.
When it opened—
Klaus's eyes widened.
It was an underground gambling empire.
Slot machines flashed in every direction.
Dice games rolled across digital tables.
Poker, blackjack, mahjong, roulette wheels, tarot duels — anything that involved risk and reward pulsed with neon and energy. Smoke lingered in the air. Drinks flowed freely.
And at the heart of it all — a circular combat ring lit with spotlights.
Two fighters clashed, fists crackling with energy as the crowd roared.
Tatsuki turned. "Wait here."
She disappeared into the chaos. A minute later, she returned—
With a bucketload of cash.
Klaus narrowed his eyes. "What… are you up to now?"
Tatsuki grinned. "We're going gambling."
"…What."
She slung her arm around his shoulder. "I'm putting you in a match and betting everything on you, kiddo."
Klaus froze. "Wait—what?"
Tatsuki's face shifted from playful to razor serious.
"This is your continued lesson—and it's centered around aura. It's a key factor in mastering the katana arts. And here, in this place… you'll trigger it faster than anywhere else."
Klaus sighed. "Fine. What do I need to do?"
"Good. Now follow me."
They arrived at the registration booth, and Tatsuki slammed the cash down.
"One million yan," she said coolly. "All on my fighter."
Gasps rippled through the room.
But no one dared speak.
Because they all knew who she was.
Except one.
A figure emerged through the smoke — graceful, commanding. Her voice smooth and laced with mischief.
"Well, well… still lighting money on fire, Tatsuki?"
A woman stepped into view.
Long dark hair. Crimson jacket. An aura of chaotic elegance. Cards floated around her as if obeying her will.
Owner of the Gambling Empire: Lady Mizue Kurogami.
Tatsuki rolled her eyes. "Still cheating your guests out of their savings, Mizue?"
They smirked and embraced briefly like old friends.
Tatsuki turned. "Klaus. Meet Mizue. Owner of this den. And my best friend."
Mizue's violet eyes scanned Klaus like a predator sizing up prey. "So you're the fighter she brought?"
Sofie immediately stepped in front of Klaus, arms crossed.
Mizue smirked. "Relax, sweetheart. I already know he's taken. I just wanted to see what has my dear friend so excited."
She tilted her head. "Cute couple."
Sofie flushed. "Tch—shut it."
Mizue laughed. "Get your fighter ready. He's up next."
---
Dressing Room – Preparation Area
Klaus stood silently as Tatsuki handed him a pair of black fighting shorts. His wrists were wrapped in white bandages. Muscles sharp and battle-scarred.
Tatsuki looked him over.
She whistled. "Whew. It's getting hot in here."
Sofie, waiting outside the door, turned red.
"Stop eyeing him like that!!"
Over the loudspeaker
"LADIES AND GENTLEMEN!! OUR NEXT FIGHTER… A MYSTERY CONTENDER FROM THE SURFACE!"
"INTRODUCING… KLAUS AETHERION!!"
The crowd roared.
Klaus stood still.
"Wait," he said. "I don't know how to use aura in battle."
Tatsuki's smile softened.
"Then let me explain."
She stepped close, voice low and focused.
"Aura is the manifestation of your soul.It bears your burdens. Shields your heart.
It responds not to logic… but to will."
She raised her hand.
A shimmering red energy wrapped around her fist from it a bit heat radiated from it.
"There are seven aura colors, each bound to a part of your spirit:
Red – Your body. Pure strength.
Orange – Your emotions. It burns like desire.
Yellow – Your willpower. Control and force.
Green – Healing, peace, balance.
Blue – Intelligence. Strategy.
Indigo – Insight. Perception and memory.
Violet – Higher thought. Transcendence."
She leaned in.
"Yours will come out when it matters.
When your soul refuses to lose."
Tatsuki placed a hand on his back. "Now go. Win."
---
Combat Ring
Klaus walked out into the light. The crowd surged with sound.
Then—
"AND HIS OPPONENT!!"
A monstrous roar filled the air.
A figure charged onto the platform, making the earth shake with every step.
Massive. Hulking. Bald. His gi torn and burnt at the edges. His silver eyebrows arched with fury.
People fainted in the front rows from the sheer pressure of his aura.
Tatsuki narrowed her eyes.
"Damn. Didn't expect him to show up tonight…"
Opponent: RAIKEN THE BREAKER.
Klaus's fists clenched.
And his soul stirred.
The fight was about to begin.
---
DING… DING…
The arena bell echoed like a war drum across the underground dome.
From the far gate, Raiken the Breaker stepped into the ring.
Each footfall was thunder. His sheer mass distorted the air. Scarred muscles rippled with every motion, and his monstrous eyes gleamed with animalistic hunger.
He didn't just walk toward Klaus.
He stalked him.
Like prey.
Klaus stood his ground, jaw clenched, every nerve on alert.
Then the referee, a lean man in black armor, stepped between them.
"Before the match begins," he said, "both of you, put these on."
He handed each of them a sleek metallic bracelet etched with glowing silver runes.
Klaus took it warily. "What's this for?"
The referee smirked. "Kid, this is a pure martial arts tournament. No elemental powers. No magic. Just blood, bone, and instinct."
Klaus's brows furrowed. He strapped the bracelet on—ZAP.
The moment it locked around his wrist, a jolt surged through his veins.
His elemental sense faded.
He staggered slightly.
It felt like a limb had been amputated.
He couldn't feel anything but his own body.
No wind. No pressure. No connection.
Just raw, vulnerable strength.
Tatsuki shouted from the corner, "Welcome to the pit, Aetherion! No tricks down here
only fists!"
Klaus rolled his neck and took a breath.
Alright… back to basics.
Klaus dropped into a familiar crouch. Hands up. Knees bent.
On the other side, Raiken's head tilted unnaturally. His eyes were locked on Klaus
Until they flicked to the side.
To Sofie.
Standing in Klaus's corner. Cheering silently. Her black-and-gold yukata still glowing in the firelight.
Raiken's tongue slid across his lips.
Lustful. Violent. Possessive.
Klaus saw it.
Saw the hunger.
And something snapped.
His body tensed. His breath deepened.
"Bastard," he growled, low and cold.
"I'm gonna kill you."
The crowd felt the shift.
Roars turned into murmurs.
Even Mizue leaned forward in her booth. "Oho… here we go…"
Raiken let out a thunderous laugh, slamming his fists together with a boom that cracked the air.
"Let's see you try, little boy."
The referee raised his hand.
"BEGIN!"
And Klaus exploded forward.
A left jab.
Then a cross.
Then an uppercut that snapped Raiken's head back.
The crowd gasped.
Klaus didn't stop.
His fists became hammers.
His legs a blur.
Elbows shattered ribs.
Knees smashed against Raiken's thighs and stomach. Blood sprayed as Klaus drove his forehead into Raiken's jaw, a brutal crack echoing through the ring.