Reincarnated in DxD With the 100X System

The sun had fully set by the time we reached the abandoned house. Its silhouette loomed under the moonlight like something ripped from a horror story—rotting wood, shattered windows, and an air that reeked of death and demonic magic.

Rias led the way with her Peerage close behind. I trailed with Aika and Mittelt, keeping a casual pace. It was clear from the start—this wasn't just a test for Issei. It was a controlled introduction to what a real devil fight looked like.

As we approached the threshold, Rias turned toward Issei, offering one last explanation.

"This is your first mission," she said. "And a good opportunity for you to see what happens when a Devil strays from their path."

She explained briefly about Peerages, the Evil Piece system, and Issei's role as her Pawn. To his credit, he was trying to listen—but I could already tell his mind was half somewhere else.

Probably on Akeno's chest.

We stepped inside.

The temperature dropped like a rock. The inside of the house was worse than the outside—walls stained with old blood, furniture smashed to pieces, claw marks gouged across the floor.

Then—her voice rang out, sultry and unhinged.

"My, my… how kind of you to visit~"

From the shadows emerged a sight that made even seasoned devils tense.

Viser.

Or rather—what was left of her humanity.

Her upper body remained that of a beautiful, voluptuous woman—bare breasts on full display, her pale skin practically glowing under the dim moonlight filtering through the broken roof. Her long black hair tumbled wildly down her back, partially hiding the inhuman grin stretching across her lips.

But that was where the beauty ended.

Her lower body was monstrous—a twisted centaur-like form with four powerful, beastly legs ending in sharp red claws. Her front limbs were humanoid but freakishly elongated, with fingers that ended in talon-like tips. A massive snake tail slithered and hissed behind her, coiled with tension.

And embedded in her stomach?

A gaping cavity lined with jagged teeth, twitching as if hungry.

Viser rubbed her own chest, licking her lips slowly.

"Been a while since I had such pretty prey~"

Issei's eyes locked on her exposed chest immediately.

"...She's naked!" he hissed, half-panicked, half-hypnotized.

Koneko stepped slightly in front of him. "Focus, pervert."

Rias held up a hand to signal caution as she stepped forward.

"Viser. You were once part of a Peerage—what happened?"

Viser let out a cruel laugh, her sharp teeth flashing. "My 'Master' was a coward. I craved power, blood, pleasure. So I took what I wanted. This body... this freedom... It's everything I ever needed."

As she spoke, magic circles began to form on her chest—right over her nipples.

Mittelt narrowed her eyes. "Wait… are those—?"

A high-pressure stream of corrosive breast acid blasted from her chest, hitting the wall beside us and instantly melting through the concrete.

Aika blinked. "...Okay. That's new."

I stepped forward, spinning my spear once and planting it into the floor.

"She's not just a stray," I said. "She's fully lost it."

Rias raised her hand, eyes flashing.

"Everyone—prepare for battle."

Viser's face twisted. Her jaw unhinged unnaturally, teeth sharp like a piranha's. Her sclera turned pitch black, and her pointed ears twitched in excitement.

Kiba drew his sword.

Koneko cracked her knuckles.

Akeno summoned a magic circle in one hand, lightning crackling across her fingers.

———

But Issei?

His eyes had immediately locked onto something else.

"Why... why are the crazy ones always so huge...?" he whispered, staring at Viser's bouncing breasts, completely distracted.

Rias turned to him, deadpan.

"Eyes up, Issei."

Everyone readied their stance, spells primed, weapons drawn.

That's when I stepped forward, raising a hand.

"Wait."

The others looked at me, startled.

"I want Issei to handle this."

The silence was immediate—and loud.

Rias blinked.

"You what?"

"I know i said to train him, but this is suicide," she added, frowning.

"I agree!" Issei waved his arms frantically. "Wait, did I miss a training arc?!"

Before the protest could build, Viser growled—and lunged. Her claws cracked the ground as she rushed in, fast and vicious.

I flicked two fingers, altering gravity around her feet. She slammed to a halt, stumbling as the air distorted.

"Mittelt. Aika," I said calmly, "go keep her busy for a bit—but don't kill her."

Mittelt's wings unfolded in a flash. "Got it."

Aika cracked her knuckles. "Finally, some real fun."

As they launched forward, Viser shrieked and engaged them in a furious clash of claws, wings, and light magic.

I turned to Issei, who was still frozen in place.

I placed a hand on his shoulder.

"Do you want to stay weak forever?"

He flinched. "No…"

"Do you want to be the Harem King or not?"

His eyes widened.

"Y-Yes!"

I grinned. "Then go prove it. Your sacred gear won't awaken on its own. Join the fight. Mittelt and Aika will back you up—just make sure you survive."

Issei's confidence flickered.

"W-Wait! I didn't say I'd fight alone!"

Too late.

I hoisted him by the collar with one hand and chucked him into the fray.

"GOOD LUCK!"

"WAAAAAAAAAHHHHHH—!"

He landed with a crash near Viser's hind legs, barely rolling to avoid a swipe from her spear. Aika burst into laughter mid-flight while Mittelt muttered, "He's so dead…"

I crossed my arms, watching with amusement.

Time to see if the Harem King had what it took… or if I'd have to fish him out of a crater later.