The moment we boarded the Gremory train, I understood—again—that devils didn't believe in the concept of "average." This wasn't a train. It was a luxury cruise ship masquerading as transportation. Velvet seats, elegant chandeliers, and a magic-infused locomotive that hummed like it was purring.
Asia, Xenovia, and even Kiba were fascinated by the polished surroundings.
Meanwhile, Gasper remained half-hidden behind my seat, trembling whenever another devil passed by.
And then there was Koneko.
She sat next to the window, staring outside with her tiny hands gripping the armrests just a bit tighter than usual. Her brows were knitted, her tail stiff, and her aura—usually calm—felt faintly turbulent.
Kiba noticed first.
"…Koneko?" he asked quietly.
Gasper peeked over the seat, blinking anxiously. "K-Koneko-chan… you're shaking…"
Koneko jerked slightly, as if snapped out of a thought she didn't want to be having. "…It's nothing," she muttered.
But her voice lacked its usual coolness.
Rias, who sat diagonally across from her, looked worried. I could see she wanted to push but held back—for now.
I said nothing. Just watched her carefully.
Something in her eyes told me this wasn't "nervousness."
It was recognition.
Fear.
Memory.
All mixed into one.
And I had a pretty good guess why.
But pushing her wouldn't help. So I simply leaned back, letting the rhythmic hum of the train fill the silence.
After about an hour, the train slowed down, the scenery shifting from crimson plains to crystalline lakes and towering sapphire spires—the demonic beauty of Sitri territory.
"We've arrived," Rias said.
The doors opened, revealing a group waiting on the station platform.
Sona Sitri.
Tsubaki Shinra.
Saji Genshirou.
All neatly lined up, wearing their official attire, looking as if they'd stepped right out of a formal devil guidebook.
Rias smiled politely. "Sona. Thank you for coming to greet us."
Sona nodded. "It's only proper. And thank you for allowing us to ride the Gremory Line. It was a great help."
Rias waved a hand casually. "You don't need to thank me for that."
Sona's gaze shifted to me.
"Hyoudou Issei."
I raised an eyebrow. "President Sona."
"You did not come for the scheduled chess practice match."
Oh. That.
I stretched lazily. "The battle of brains wears me down, Sona-kaichou. After I return from this Underworld trip, I'll come by and lose properly."
A twitch appeared at the corner of her lips. "You make it sound like the result is predetermined."
"Well," I said with a grin, "I know when I'm outmatched."
Tsubaki stifled a laugh behind her hand.
Sona folded her arms. "Then I expect you. And since you will be in the Underworld… perhaps you should visit the Sitri residence. We have things to discuss."
Rias' eyes narrowed just a fraction.
Sona looked directly at her. "Is that acceptable, Rias?"
Rias smiled a smile that was very sweet—and very threatening.
"If he wishes to go, I won't stop him."
Which translated to: I'll absolutely stop him.
I shrugged. "I'll drop by later. You owe me a revenge match."
Sona nodded, satisfied. "Then I'll prepare the board."
With formal bows, the Sitri group departed, the crystal-blue scenery disappearing behind them as the train began moving again.
As we traveled deeper into Gremory territory, the lakes shifted to crimson forests, volcanic plains, and floating islands shaped by demonic magic. Even Asia stared in awe, hands pressed against the window.
"This world is so beautiful…" she whispered.
Xenovia nodded beside her. "It is more… orderly than I expected."
"I was expecting fire everywhere," Gasper murmured.
"You watch too many human movies," Kiba said.
Rias chuckled.
But before the peaceful atmosphere could settle, the train jerked—hard.
The brakes screeched, runes along the walls flickering.
"What happened?" Rias stood instantly.
Azazel appeared behind her like he'd simply materialized from the air. "Change of plans. We're stopping here."
He held up a glowing white scroll.
"Meeting request from the Norse. Emergency strategy discussion. Khaos Brigade-related."
Rias' expression hardened. "Right now?"
"Right now," Azazel confirmed. "Sirzechs wants us present."
Before anyone could process it—
A magic circle surged under our feet.
"Wait—!" Rias reached out.
But the spell activated.
And in a flash of blue-black light, all of us except Rias and Azazel vanished.
We landed in a massive circular arena made of obsidian stone and glowing runes. The air vibrated with overwhelming draconic pressure.
Gasper dropped to the floor screaming. "W-We're going to die!"
Before anyone could calm him—
A gigantic flame ignited in front of us.
A colossal dragon landed, shaking the entire arena. Horns like giant blades curled from its skull, wings spread like a castle-sized cloak, scales burning with magic power.
Its roar felt like it punched straight into our bones.
Tannin.
A former Dragon King.
Now a devil serving the Gremory.
And one of the strongest beings in the Underworld.
A grin stretched across my face instantly.
"Oh hell yeah," I said. "I've been waiting for this."
No fear.
No hesitation.
Only excitement.
Akeno stepped forward, lightning crackling between her fingers. "Everyone! Form up! Assume hostiles!"
Koneko leapt beside me, fists clenched. Kiba drew his sword, Xenovia unsheathed Durandal with divine force, and Gasper—despite trembling—activated the faint beginnings of his time-stopping field.
I summoned Ascalon, the dragon-slaying blade that hummed with holy resonance.
The dragon lowered its head, eyes glowing with predatory interest.
"Here it comes!" Kiba yelled.
The battle erupted instantly.
Xenovia slashed the air, sending a wave of holy energy. Koneko dashed across the arena, fists coated in Touki. Kiba's speed blurred into white streaks. Gasper—trying not to faint—froze the dragon's claw for half a second.
And I dashed forward with Ascalon, sliding under its swipe and slashing hard—
A deep cut tore open along its scales.
"Tch—tough bastard," I muttered, admiring the dragon's sturdiness.
Tannin roared, the force sending shockwaves that blasted the ground apart. Akeno responded with thunder that exploded across his wing, forcing him back slightly.
But even with all our efforts—
He was still far beyond us.
With a flex of his wings, Tannin unleashed a burst of fire so powerful that Kiba had to grab Gasper and leap aside, rolling over scorched earth.
Xenovia was forced back by sheer force, Koneko's fists cracked the ground trying to parry a claw, and even Akeno gritted her teeth as she protected us.
Still—
None of us were backing down.
As I swung Ascalon again, fire bursting around us, I laughed.
"This is the best training exercise ever!"
Before Tannin could unleash another firestorm—
A crimson barrier stopped him.
Rias floated down gracefully. "That's enough."
Azazel followed behind, smirking. "You kids did better than expected."
"What is this?" Kiba asked.
"A training drill, I arranged." Azazel said.
Tannin shrunk slightly, folding his wings.
"A fine group," he said. "Especially him." His reptilian eyes landed on me. "You cut me, boy."
I held up Ascalon with a smirk. "Dragon-slaying sword. It'd be weird not to."
The giant beast laughed, a deep, thunderous sound.
Azazel patted my shoulder. "Prepare yourself, Issei. This guy's in charge of your training."
I grinned wider.
"Good."
~~~
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