Some might think this was the perfect chance for Lucian to kill Issei and use the skill Extractor on him — after all, taking the Red Dragon Emperor for himself would've been a massive power boost.
But Lucian had no such thoughts.
Not only was he against killing innocents, but he also doubted that Extractor would even work on a Longinus. Those sacred gears were divine anomalies — more artifact than ability — and meddling with them felt like tempting cosmic irony.
Besides, it wasn't as if he was short on power. His Essences were more than enough power creep for him.
In just a few more days, he'd receive another one. And if the previous three were anything to go by… he could wait.
He leaned back on the park bench, fingers laced behind his head as he stared toward Kuoh College — the supposed hub of supernatural activity.
The problem?
He was twenty-three.
Too old to pose as a student, too young to pass as a teacher.
"Maybe a substitute? Or… a mysterious foreigner with amnesia?" he muttered, half-joking, half-serious. His mind wandered through increasingly absurd plans until—
Thud!
Pain exploded at the back of his head.
The world spun.
Lucian's last thought before blacking out was an eloquent, Oh, for f—
---
A Few Weeks Earlier…
Sakurada Youta had been an ordinary man once. At least, until he wasn't.
Summoned against his will by one of the Western Kingdom of the Cardinal World, he awoke in a dim stone chamber, shackled and collared, surrounded by robed mages.
Like all summoned beings, a Skill manifested within him — a reflection of his soul.
For Youta, it was Unique Skill: Reverser.
The ability to invert, alter, and recreate any magic he understood.
And so, the slave became the master.
It started small — reversing the binding spell of the slave collar.
Then, with a twisted grin, he turned the spell on the Archmage who'd summoned him. The old man's eyes glazed, his voice breaking as he knelt.
From there, it was simple.
Each new victim helped him subjugate the next.
The once-great tower of mages fell silent under Youta's command.
He lived like a king.
Silken sheets. Golden goblets. The kind of luxury only those without empathy could truly enjoy.
And, of course, women — broken and enslaved by the collars he so effortlessly manipulated.
For a time, he thought himself untouchable.
Until one day, a trembling guard escaped and reached the royal city.
What followed was inevitable — soldiers, spells, siege engines, and a noose tightening around his little kingdom.
Cornered, Youta panicked. But panic breeds invention.
He reversed the summoning array itself — an act so suicidal even his slaves hesitated to assist.
And yet… it worked.
He vanished in a flash of light, reappearing back on Earth — his wrists bare, his pockets heavy with stolen slave collars.
---
Back in Japan
For days, Youta tested his stolen magic in secret, slowly realizing this world too had its hidden wonders.
Demons, spirits, magicians — all living in plain sight.
He also awakened another gift, born from crossing worlds:
Unique Skill: Seer.
The ability to perceive a person's power level, potential, weaknesses, and whether certain magics or items would affect them.
That skill became his obsession.
It led him to Kuoh College, where he saw the highest concentrations of power he'd ever encountered. Beautiful girls with impossible auras — predators disguised as students.
One in particular caught his attention: a crimson-haired girl whose magic shone like the sun.
Rias Gremory.
Powerful. Beautiful. Perfect.
He almost salivated at the thought — until Seer's warning stopped him cold.
[Result: Enslavement collar — Ineffective.]
So he waited.
Watched.
And one day, near the college gates, he found someone else — a man standing off to the side, observing the school like a visitor from another world.
High potential. Low power.
[Result: Enslavement collar — Compatible.]
Youta smiled, a twisted thing born of hunger and habit.
---
Lucian never saw the blow coming. One second he was planning how to sneak into the school, the next — darkness.
When he awoke, it was to the sight of peeling wallpaper, stale air, and a man grinning above him.
Youta.
The grin was too wide, too eager — like someone admiring a new toy.
Lucian blinked, disoriented.
"...Did I get kidnapped?" he muttered, more to himself than the stranger.
"Awake, are we?" Youta said pleasantly, though his eyes were cold. "Good. Makes this easier."
Lucian sat up slowly, instincts already screaming danger. A faint metallic chime echoed as he moved — something heavy around his neck.
A collar.
Oh, hell no.
Youta extended his hand. "Kneel."
Lucian raised an eyebrow. "...You're serious?"
When Lucian didn't move, Youta's brow twitched. "I said—kneel!"
Nothing.
The collar pulsed faintly once, then dimmed.
Deep inside Lucian, the power of Essence of Protection worked without even informing Lucian and simply nullified the Coller, as it did count as mental Manipulation.
Youta froze. "That… shouldn't be possible."
Lucian stood, edging toward the door. "Listen, man, I don't know what kind of weird sex dungeon you're running here, but I'm leaving. Preferably with all my organs intact."
He grabbed the knob — locked.
Of course it was.
He considered breaking it down, then remembered something.
Teleportation. He could just—
The door exploded inward.
A rush of air, a flash of crimson and silver.
Youta staggered back as a group of girls stepped through the smoke — each radiating power and authority.
At the front, a composed young woman with short dark hair adjusted her glasses. Her voice was cool, precise.
"President, it seems you were right. This is the man who's been enslaving people."
Tsubaki Shinra.
Behind her, the President herself entered — calm, beautiful, eyes sharp with icy fury.
Sona Shitori.
Her gaze swept the room once, assessing everything — the collars, the magic residue, the unconscious fear twisting on Youta's face. Then it softened slightly as it landed on Lucian.
"Another victim," she murmured. "He looks unharmed… for now."
Lucian blinked, still half-crouched near the doorway, processing the sudden chaos. "...I swear I didn't do anything."
Obviously, he recognised them, and he seriously didn't want them to think he's some SM slave or something, that'll be a really bad first impression.
Sona gave him a measured look — not distrustful, just evaluating. Then she turned her full attention on Youta.
The man snarled, desperation bleeding through his calm mask. "You devils think you can judge me? You do the same! You enslave others too!"
Sona's eyes narrowed. "We offer contracts. Consent. What you've done is slavery."
Well, technically a lot of Devils didn't do the whole consent thing but yeah ut was true for Sona and Rias and some other Devils too.
Youta opened his mouth to retort — but the faint hum of Tsubaki's mirror spell silenced him, locking his body mid-motion.
Sona exhaled slowly, letting her composure settle like steel. "Inform Rias. Tell her the case is closed."
She looked once more toward Lucian. "We'll remove that collar shortly. You're safe now."
Lucian hesitated, then managed a weary smile. "Thanks… I was starting to think Japan had gotten way kinkier since I last checked."
Tsubaki blinked. Sona sighed, pinching the bridge of her nose.
"Let's get him out of here," she murmured. "Before he says anything else."
It took only minutes for the Peerage to clean up the scene, but the echoes of that day would ripple far longer.
For Youta, it marked the end.
For Lucian — it was merely the beginning of his entanglement with Kuoh's devils.
A/n: I'm thinking of changing MC's Race, a simple idea would be him becoming a Devil but as he has Essence of Protection, he'd simply be immune to the enslavement and even entering the Peerage itself, he'd evolve into a Devil but not as a subordinate and he could maybe act like he's in her Peerage but is not or something like that. Or I could use one of the Essences to change his Race... Or there's a Essence that can help you have multiple Races or stuff. Which route do you prefer?
Lastly I'd love your suggestions for any Essences you'd like to see in the story. You can find all the Essences on Google and I'd also give my thanks to all the Authors like Triggerhappy Jaberwocky, NorthSouthGorem, Cliff999, TroyX, OverReactionGuy, Kinglugia, Zediekiel, Jus4532, Wheenesss, and Celestial Dragon and everyone else.
Especial thanks to Jirachi for Essence of Protection, NorthSouthGorem for the Essence of Nomad and Monx999 for Essence of World Merge.