DxD : Actually Satan..?

[Regular chapter]

Leo stood in front of a confused soldier, who still had a rifle shakily aimed at him.

"Don't shoot," Leo said casually, giving a small two-fingered wave. "I'm allergic to bullets. They give me the urge to commit arson."

The soldier blinked, unsure whether this was a threat, a joke, or both.

Then Leo began to sink into the concrete, his feet dissolving into the floor as though he were a shadow melting into the ground. His body followed, casual as could be, like Zetsu sliding into the dirt with nowhere urgent to be.

"Bye now," he said, his smirk the last thing to vanish, accompanied by a faint bloop.

The soldier stared, mouth agape, gun still raised.

"…What the actual fuckery...," he muttered, wallong back to his post and lighting a cigarette with shaking hands. "Nuh-uh. Nope. ."

---

Meanwhile, Illya was humming softly to herself as she walked down a pristine hallway, her hoodie swaying with each step.

She passed flickering fluorescent lights and utterly ignored the alarms ringing in the distance.

She strolled up to another soldier, crouched behind a desk, radio in one hand and a taser in the other.

He flinched as she tapped him gently on the shoulder.

"Excuse me, could you point me to the laboratories?" she asked, smiling sweetly.

The man stared at her like she'd grown a second head. "W-what?"

"I said, labs. Down that way?"

"Uh… t-two lefts and a right…"

"Thank you~!" she said, skipping off like it was a school hallway and not one of the most secure facilities on Earth.

A few seconds later, someone fired at their parked plane—perhaps thinking they'd finally hit something.

The moment the bullet pinged off the hull, the plane responded.

A small laser turret unfolded from beneath the cockpit with an almost polite whirr.

Zzzzap.

The would-be shooter dropped, a clean hole in the center of his chest and a faint smell of fried meat in the air.

---

Below ground, Leo moved like a shadow in the data. Invisible to cameras.

Unseen by sensors.

He scrolled through the country's best-kept secrets like they were tabloid headlines.

He passed Vault 7B — "Sealed Item: Excalibur Fragment (Unconfirmed)"

Opening it, Leo found a rusted piece of rebar with "EXCALIBUR?" scrawled in Sharpie.

He made a face. "Y'all deserve to be scammed..."

a box labeled "Classified Organic Core - Unknown Origin. Possibly linked to Outer Gods."

Inside was what looked like a shriveled peach pit floating in blue liquid. Leo scanned it, paused, and knew it also was just a extremely mana poisoned fruit.

Further in, another chamber contained "Mystic Eye - Model 7D - Kill Limit Variant."

The eye hovered in a suspension field, connected to machines and slowly rotating.

Leo could understand its ability to be :- Each eye permits seven instant-kill effects. Eye goes blind after usage.

Leo copied the blueprint without hesitation.

---

Then came something unexpected.

Another vault, buried beneath a foot of security protocols and even more of bureaucratic incompetence, held an ancient schematic labeled in hand-scrawled notes: WEAPON CONCEPT.

It was black barrel.

The actual barrel wasn't here.

But the blueprint—poorly translated from some ancient Atlas documents—was.

Leo's eyes widened slightly.

This wasn't the Black Barrel, not exactly.

But it was a primitive version—more of a condensed mana reactor with a failsafe function designed to annihilate spirit-based life.

A prototype that, while crude and unfinished, used pure mana conversion rather than any normal magical core.

The Americans hadn't been able to build it. Leo could tell by the thirty red-marked "FAILURE" stickers across every page.

"...Close," Leo muttered, reverently copying it.

He grinned like Rom. "Could build a city-killer with that."

---

Another strange find was a long-forgotten crate containing an Aegis-class Mirror Shield, which supposedly deflected any spell under the rank of A.

But it was mostly decayed in terms of mystery only possible to qualify as a museum peice.

The final artifact that gave him pause was an unlabeled container in the back of Section E. Inside was a single twig—gray, dead-looking, faintly warm

Leo stared at it, and in that moment, his smile disappeared.

"…Found you. Specimen E."

---

Meanwhile, Illya had most definitely not found the laboratories.

Instead, she turned a corner and ran headfirst into what could only be described as a small army of magi in lab coats and powered robes, all standing dramatically like they were in some mid-budget magic anime.

Runes floated, staves glowed, and one of them even had a ceremonial dagger shaped like a crescent moon.

"You're trespassing on government property!" one shouted. "Surrender or prepare to—"

CRACK.

Illya's punch caught him square in the jaw, sending him flying into a vending machine.

The rest hesitated.

That was their best talker.

Illya grinned, already bouncing on her heels, a little spark of something wild in her eyes.

"Come on! I dare you!"

A barrage of spells followed—lightning, ice, fire, wind.

The hallway lit up like a festival of destruction.

When the smoke cleared… Illya was still standing.

Her hoodie was a little torn, a small trail of blood ran from her nose, and a burn sizzled across her side.

But even as they watched, the wounds sealed themselves, her body knitting back together like a stubborn bad habit.

"You done?" she asked sweetly.

One brave soul launched a binding rune.

Illya caught it in her hand and crushed it with pure magical resistance.

The next few minutes could only be described as painful education for the magi.

Bones cracked. And muscles got torn.

At one point, someone screamed "Not the face!" as Illya swung him by the ankle into his colleague.

Through it all, she laughed—not cruelly, just with sheer joy.

The kind of unrestrained, gleeful release only someone who had never gotten to run, fight, or feel her own strength before could understand.

The end result?

A hallway full of unconscious or groaning magi, and Illya standing victorious on top of a toppled filing cabinet, slightly out of breath but beaming.

"Best detour ever," she said.

---

Illya wae enjoying herself.

Sure, she'd been ambushed twice in a row after politely asking for directions, but her new body felt amazing.

Strong. Durable. Light.

She hadn't even needed to think about using magic—her fists had done all the talking.

Just like Berserker used to.

She turned the corner of another wide hallway inside Area 51's lower levels, now a maze of steel walls and buzzing lights. "Excuse me," she said with a bright smile, spotting a man in a white coat who looked too calm to be one of the twitchy scientists she'd already smacked.

He stiffened. "Y-You're…the intruder …?"

"Yes. I'm looking for the artifact labs—"

The floor dropped from beneath her mid-sentence with a hydraulic hiss and a puff of compressed steam.

"—Again?!"

---

She landed cleanly, bending her knees and springing upright in a reinforced steel chamber that reminded her of a zoo enclosure built by people who'd never seen a living thing before.

On the far side, sealed behind a thick transparent mana-barrier, was… a thing.

It was massive—at least twenty meters long, wide as a tank, with armored green-black scales that shimmered like oil under artificial light.

Each of its seven heads snarled in perfect unison.

Thick crocodilian jaws, twisted and mutated, blinked one at a time.

Each eye glowed with a different magical hue—red, blue, violet, yellow.

A seven-headed crocodile.

Its tails slammed the floor behind it, leaving craters.

Illya just blinked. "You've got to be kidding me."

Above her, a synthetic voice announced with eerie calm:

"Test Subject 66: 'Unkmown Entity' detected. Initiating Beast of Revelation Vessel Trial. Releasing containment locks."

Several magitech restraints hissed and folded away. The barrier dropped.

The beast charged.

It moved like a train off the rails—too fast for its size, too quiet for its weight.

Illya leapt back just as the center head lunged for her neck.

She landed with a hard thud, skidding across the metal floor and slamming into the wall.

Pain flared in her shoulder. She grinned.

"Oh, you're tougher than the last guys. Good."

The next moment, she charged forward herself.

The leftmost head spewed black fire—Illya ducked under it and punched it in the jaw, sending it crashing sideways into its sibling.

She turned, grabbed one of the center heads by the teeth, and twisted.

It thrashed violently, slamming her into the wall.

Still, she didn't let go.

With a growl of effort, she tore the head off, snapping it free in a spray of black blood and sparks. It wasn't organic.

Not entirely. Metal veins pulsed inside the beast's flesh—half-machine, half-monster.

The heads reacted in sync, biting, slashing. One latched onto her side.

Illya grimaced, then grabbed the offending snout and crushed it with a loud crack. Another lunged.

She caught it mid-air and drove it into the floor like a sledgehammer.

Two more heads coiled around her limbs.

She flexed, muscles bulging unnaturally. Red lines on her skin glowed faintly as she used mana reinforcement.

With a shout, she broke free—tore through the grip and jumped high, landing on the creature's back.

It tried to throw her off.

She slammed her fists down in a rhythm: one, two, three, four—

Heads fell. The beast shrieked in agony.

Its last head tried to bite her shoulder.

Illya turned her neck slightly, caught the head in her hand, and drove it through a wall.

Silence.

Steam rose from the carcass.

The chamber flickered with damaged lights.

Illya stood there, panting slightly, covered in ash and ichor—but her smile was relaxed.

"This is what safety and confidence feels like," she muttered.

She brushed herself off, just in time for Leo's voice to whisper inside her head.

"Found Specimen E. Prepare to be teleported."

"Huh?" she said aloud. "Wait, teleportation? Isn't that like—super difficult and—"

Pop.

Golden-red energy shimmered around her, and she vanished from the chamber.

---

Elsewhere, in the artifact labs deep in Area 51, Leo was quietly looking through shelves of relics and containment units.

He paused, glanced to the side—

—and smiled faintly.

"She'll arrive in 3... 2... 1..."

The golden glow of teleportation faded just in time for Illya to materialize in the middle of a chamber filled with consoles, hovering glyphs, and one very smug devil crouched low in the shadows.

"BOO!" Leo said, his voice sharp and sudden.

Illya yelped, startled, and reflexively swung a fist at him.

It connected squarely with his cheek—only for her to recoil immediately, clutching her hand. "Ow, ow, ow!! What are you made of?!"

Leo, completely unaffected, just raised an eyebrow. "That's what you get for trying to hit your superior."

He reached out and flicked her forehead with two fingers. A sharp flick. She staggered back a little with a squeak, rubbing her head indignantly.

"Rude," she muttered under her breath.

Leo stood up and turned back toward the containment unit behind him.

Leo smiled.

"This thing," he said, "is a living computer… a living factory… and a living weapon."

Illya blinked. "You mean, like a Swiss Army knife?"

"No. Like a goddamn Swiss Army knife apocalypse."

He glanced at her, eyes glowing faintly. "This thing was able to take on the concept of humanity. Not just mimic it. Become it. The fact that it didn't get rejected by the world's foundation proves how deeply it assimilated the idea."

Illya looked back at the floating figure with a newfound curiosity. "So it's… like a shapeshifter?"

Leo shook his head. "It's far beyond that. It's an adaptive machine. And somehow, someone managed to trap it in here. That's almost more impressive than the specimen itself."

"But it's just a twig", Illya said pointing at it indignantly.

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Power Stones and Reviews please