High School DxD: The Lucifer's Devil Trigger — Chapter 3

Chapter 3: Devil Trigger

Levi committed the reaction to memory. At the very least, Sirzechs’ response proved he could be tentatively trusted.

Silence stretched across the room for two heavy seconds. Sirzechs finally stood, his expression freezing over with an icy, absolute authority. Grayfia tensed, her posture shifting as if anticipating a sudden strike, but the Crimson Satan merely offered a shallow, respectful bow toward Levi.

“Thank you for bringing this to my attention. If possible, I would like any further information you might have regarding Rizevim.”

Levi offered a polite smile, thoroughly unsurprised. The reaction fell perfectly within his calculations. In his past life, the fandom had practically run the joke into the ground that Sirzechs was the reincarnation of a benevolent god. He was reasonable to a fault.

Even if Sirzechs had acted unpredictably, Levi was far from defenseless. Before stepping into the room, he had discreetly anchored a Summoned Sword in the shadows near the exit. Unlike Vergil’s original technique, his variant allowed him to instantly teleport directly to the blade’s location. Paired with Yamato’s innate ability to sever the fabric of space, he could tear open a rift and vanish back to his stronghold before the Satan could blink. From there, he could simply detonate the magical restrictions Rizevim had left behind, alert the old fox, and instantly ignite a powder keg between the two factions.

Naturally, that was a last resort. Since the diplomatic route was proceeding smoothly, he would continue playing the part of the loyal double agent.

“Of course. It is no trouble at all, Lord Sirzechs.” Levi leaned back slightly, laying out the rest of his carefully curated hand. “I do not know the exact details of Rizevim’s departure from the Underworld. However, before he vanished, he mentioned an organization. He called it the Khaos Brigade.”

Sirzechs’ eyes narrowed slightly.

“He intends to gather the remnants of the old devils and let them develop in the shadows,” Levi continued, his tone even. “When the critical moment arrives, he plans to personally lead them to reignite the devil civil war. I do not know exactly which noble houses have signed contracts with him. But I recall him mentioning the Naberius Clan. Something regarding an artificial extraordinary experiment.”

Levi let a subtle frown touch his features. He wasn’t a master actor, so he kept his expressions minimal, projecting the image of a man repeating dangerous terms he didn’t fully comprehend.

In truth, Rizevim would never share such critical secrets with a supposed pawn. Every piece of intel Levi just dropped came directly from his knowledge of the original timeline. As for whether the Naberius Clan was actually colluding with Rizevim right now, he couldn’t be entirely certain. But he knew one absolute truth—the Naberius Clan was actively conducting abhorrent artificial extraordinary experiments, and their current test subjects were the two assets he had already claimed for his future peerage: Kuroka and Shirone.

“Is that so.” Sirzechs gave a slow nod, offering no immediate promises but showing no signs of doubt. “I have noted your words. We will launch a covert investigation into these matters. The clues you have provided are very useful, but you must exercise extreme caution. When you are by Rizevim’s side, you cannot afford to show a single flaw. One misstep, and your life will be forfeit.”

“I understand. And I genuinely intend to maintain my cover as the mole Rizevim planted within our ranks. I will help the Underworld keep an eye on him.” Levi’s gaze met the Satan’s. “After all, I have no desire to see the Devil race plunge into another catastrophic war.”

That much was the absolute truth. He needed a stable, peaceful environment to trigger his system check-ins and consolidate his power.

Sirzechs, oblivious to the existence of the system, heard only the earnest plea of a devil focusing on the safety of their race. The Crimson Satan’s demeanor softened considerably, a deep sense of camaraderie forming in his chest. He felt as though he had found a rare, like-minded ally within the fractured ranks of the nobility.

After a brief exchange of pleasantries, Levi excused himself, citing the need to keep his visit strictly low-profile. He requested Grayfia to escort him out.

The moment he stepped into the corridor, a familiar chime echoed in his mind.

[Check-in Reward: Devil Transformation (Devil Trigger)]

Levi paused mid-step. Having consecutively acquired Yamato and the perfected Summoned Swords, he found himself surprisingly unfazed by the sudden acquisition of a demonic transformation.

‘Just the standard Devil Trigger form, huh…’

Levi clenched his right hand, silently commanding the system. He activated the Devil Transformation.

A surge of raw, crackling energy erupted beneath his skin. A phantom coat of deep, abyssal blue manifested over his shoulders, woven from pure demonic aura. Unlike Vergil’s full metamorphosis that shed all humanity, Levi’s form remained partially grounded. A pair of jagged, swept-back devil horns breached the crown of his head. complex, luminescent blue markings crawled up his neck, tracing the sharp lines of his jaw. His hands and feet shifted, armored in dark, scaled demonic plating, while his eyes ignited with a piercing, ethereal blue fire.

‘Every physical stat is amplified… The sensation is remarkably similar to a Sacred Gear’s Balance Breaker.’

In the Lucifer Clan, Levi had been dismissed as a useless waste, but his baseline demonic power had never truly fallen below the standard of a High-Class Devil. The moment the Devil Trigger took hold, the dormant magic within his veins roared to life, expanding exponentially. He gauged the surging pressure. He was easily brushing against the absolute peak of an Ultimate-Class Devil.

And this was merely his first time activating the form. With time, mastery, and further integration…

‘Once I fully synchronize with this state, I might possess Satan-class combat power right out of the gate.’Levi let out a quiet breath, dismissing the transformation. The blue aura shattered into fading embers. Had this reward triggered specifically because of his interaction with Sirzechs? Originally, he assumed a standard Devil Trigger would only elevate him slightly. He had planned to rely on unlocking the Sin Devil Trigger to truly breach the Satan-class threshold.’Tch. It’s significantly more ferocious than I anticipated.’

He summoned Yamato, the dark scabbard resting comfortably in his grip, a faint thrill of anticipation bleeding into his usually calm eyes.

“Lord Levi, are you heading out?”

Grayfia rounded the corner of the grand hallway, her silver hair catching the ambient light. She noted the sword in his hand, her voice carrying its usual pristine neutrality.

“Hmm… I wouldn’t say I’m going alone.” Levi turned to face her. “If it isn’t too much trouble, could you accompany me on a brief trip to the Naberius Clan?”

At the mention of the name, Grayfia’s expression remained perfectly sculpted ice, but a microscopic shift occurred in her silver eyes. “The artificial extraordinary experiment you mentioned to Lord Sirzechs… correct?”

“Correct.” Levi took the lead, his boots clicking rhythmically against the marble floor. Grayfia fell into step smoothly behind him.

“I understand Sirzechs’ position perfectly,” Levi murmured as they approached the grand exit. “It isn’t that he doubts my intel. It’s that the political ramifications are too massive. Once he returns, he has to convene with the other Satans, draft a consensus, and handle the bureaucratic nightmare of the Underworld. He has to proceed with caution to avoid alerting the enemy.”

He pushed the heavy doors open. The cool, biting wind of the Underworld swept over them.

“Lord Levi, the nobles on their side…” Grayfia began, her voice dropping a fraction.

“You don’t need to spell it out. I know.” Levi stopped on the grand staircase, turning to look directly at the Silver-Haired Queen of Annihilation. “Whether it’s the Reformist Faction or the Old Satan Faction, they are still political machines. And a faction cannot operate as a dictatorship. The hardliners of the Old Satan Faction are largely gone, leaving the internal voices of the Reformists increasingly chaotic and divided.”

He looked out over the sprawling demonic landscape. “Sirzechs might want to trust me. He might even know that certain atrocities need to be purged immediately. But his hands are tied by the very crown he wears. He cannot act unilaterally simply because he is the Satan Lucifer.”

“Then you…” Grayfia caught herself, the realization clicking into place.

“Me?” Levi chuckled, a dry, hollow sound. “I carry the surname Lucifer, but I am not the Satan. More, I am officially a remnant of the Old Satan Faction. No matter what atrocities I commit today, the political fallout will simply be billed to the Old Faction’s tab.”

Grayfia closed her eyes, offering no rebuttal.

“At the very least, no one in the current administration will publicly jump out to condemn you,” she noted quietly.

“As long as the surface remains undisturbed, I couldn’t care less. How they curse my name in the shadows is irrelevant.” Levi turned his back to the castle, his gaze locking onto the distant coordinates of the Naberius territory.

“I live my life on my own terms, doing exactly what I deem necessary. The opinions of others are none of my concern. Let’s go, Grayfia.”

“Understood, Lord Levi.”

Deep beneath the opulent, towering castle of the Naberius Clan lay a sprawling, subterranean nightmare. The exterior projected the majestic dignity of high nobility, but the catacombs below reeked of sterile chemicals, old blood, and unchecked madness.

This was the cradle of the artificial extraordinary project.

In the modern Underworld, only two beings held the true title of extraordinary: Sirzechs Lucifer and Ajuka Beelzebub. Rizevim had long since been written out of the equation. The vast majority of devils had accepted their genetic limitations, bowing to the overwhelming might of the current Satans.

The Naberius Clan refused to bow. Their ambition was a festering rot. They sought to shatter the ceiling of demonic power, forcefully engineering a synthetic extraordinary through agonizing biological alchemy. If they succeeded in producing even three stable subjects, they would instantly possess the ultimate military deterrent. They could crush the Reformists, eradicate the Old Faction, and seize the thrones of the Underworld for themselves.

That singular, intoxicating vision of the future had driven the entire clan to the brink of insanity. What began as a fringe theoretical project had devolved into mass vivisection and endless live-subject testing. The researchers in the white coats were no longer devils; they were butchers obsessed with a singular goal. Success at any cost.

In the deepest, darkest cell of the dungeon, Kuroka sat huddled in the corner, her arms wrapped fiercely around her younger sister. Shirone was asleep, her small frame pressed against Kuroka’s chest, her tiny hands gripping her older sister’s torn clothes even in unconsciousness. Kuroka’s face was smeared with grime and dried blood, yet as she looked down at the sleeping girl, she forced a soft, fragile smile.

‘Devils… they’re all fucking monsters.’

She had witnessed the descent firsthand. She had watched the Naberius researchers transition from cold indifference to rabid obsession. In her eyes, this was the true, inescapable nature of the Devil race.

Kuroka gently stroked Shirone’s white hair, her fingers brushing against the small cat ears twitching in her sleep. The resolve hardening in Kuroka’s chest felt like solid iron.

‘If the flames of this hell only consume me, I won’t regret burning.’

She leaned down, pressing her forehead against her sister’s, her voice a broken whisper. “But you’re different… Shirone. You are the one thing in this world I absolutely cannot lose.”

Her decision was finalized. She would tear this facility apart with her bare hands if it meant getting Shirone to the surface.

Before she could even shift her weight, a blinding surge of blue light pierced the gloom of the cell. The ambient magic in the air warped violently, compressing into a suffocating pressure. Kuroka moved on pure instinct, violently shoving Shirone behind her. Her claws unsheathed with a sickening snikt, her twin tails bristling as she dropped into a feral, desperate combat stance.

The blue light flared to a crescendo, and two silhouettes stepped out from the spatial tear.

The sudden influx of raw power jolted Shirone awake. She rubbed her eyes, disoriented and terrified by the blinding light. “…Sister?”

“Don’t make a sound. When I say run, you run as fast as you can,” Kuroka hissed, her Senjutsu flaring as it locked onto the powerful aura standing just feet away.

“Go to hell!”

Magic and Senjutsu violently fused together, igniting black, corrosive flames at the tips of her claws. Kuroka lunged, driving a lethal strike directly toward Levi’s throat.

But compared to the terrifying criminal she would become in the future, this Kuroka was tragically slow.

Levi didn’t even draw his sword. He had already activated the Devil Trigger before teleporting. Demonic plating coated his arm as he casually reached out, his hand snapping shut around Kuroka’s wrist like a steel vice. The kinetic force of her charge died instantly. He pulled her slightly forward, forcing her golden, panicked eyes to meet his calm, glowing blue gaze.

Kuroka bared her fangs, thrashing wildly to break his grip, but she couldn’t move an inch.

“Easy there,” Levi said, his voice a low, resonant hum that cut through her panic.

Kuroka froze, her breath hitching as the sheer weight of his aura washed over her.

“There is no need to be afraid anymore,” Levi continued, his grip loosening just enough to show he meant no harm. “Your days of suffering in this pit are over. Leave the rest of this to me.”

Two translucent screens materialized in his peripheral vision.

[Check-in Target (Kuroka Toujou): Subdue Kuroka Toujou.]

[Check-in Target (Shirone Toujou): Pat her head.]