Distributing devil flyers was the first job every devil working in the human world had to go through.
As Leo had explained before, in the modern age, no one went out of their way to hunt down forbidden tomes and draw complex summoning circles just to perform an ancient ritual to call upon a devil and make a contract. Those days were long gone. Now, devils relied on flyers inscribed with simplified magic circles—delivered directly to human homes—as the foundation for all their modern activities.
Normally, this task was handled by familiars. Devils rarely bothered with such trivial errands themselves. But High-Class Devils often made their new servants do these low-level jobs for a while, both as training and as a form of discipline. Only after mastering the basics would a servant begin taking proper requests from humans—those whose desires resonated with the devil's power—and earn rewards through completed contracts.
As a newly reborn devil, Yukino naturally had to start from this step.
Of course, that didn't mean she had to stand on busy streets like a part-time promoter, smiling and handing out flyers to passersby. Her job was far simpler: she only needed to deliver them at night, slipping each one into the mailbox or door slot of its designated target while the city slept.
"So all I have to do is deliver these while people are asleep?"
When Yukino heard that, she let out a small sigh of relief.
If she had to stand in public, smiling and making small talk with strangers… that would've been pure torture for someone like her.
"We don't have much choice," Leo explained. "Unlike familiars, we devils can only act at night. The daytime belongs to angels and gods. If you dared to hand out devil flyers in broad daylight, you'd better pray you don't run into someone from the Church. They wouldn't hesitate to send exorcists after you."
"Don't make it sound so terrifying!" Yukino stiffened, irritation flashing in her voice. "I have no intention of dying again!"
Even now, the memory of that night—when Varden had driven a holy spear straight through her body—still made her shudder.
For most people, surviving a near-death experience would be a brush with mortality. But Yukino hadn't almost died—she had died. And the feeling of her life slipping away had been anything but pleasant.
She had no desire to relive that horror.
"Then take this."
Leo suddenly pulled out a metallic bracelet and handed it to her.
"What's this?"
Yukino turned it over in her hands, curious.
"A light detection device," Leo said. "It can sense high concentrations of light power nearby. If it starts beeping, that means there's either an angel, a fallen angel, or an exorcist from the Church capable of wielding light weapons nearby."
He smiled faintly. "Chiba City is still the Church's territory. Devils can't operate freely here. This will help you avoid danger."
It wasn't anything particularly rare—just an old tool Leo had used when he was younger, given to him by the devil who'd once mentored him in the Underworld. Practical, but far from precious.
"You're not using one?" Yukino asked, tilting her head.
"I don't need it anymore." Leo smirked with quiet confidence. "These days, it's the Church that avoids me, not the other way around."
Even though exorcists could wield the light of angels in combat, none of them were foolish enough to pick a fight with a High-Class Devil.
No matter how skilled or battle-hardened they were, humans were still just flesh and blood. Against a High-Class Devil, they needed to act in teams if they wanted any chance at victory.
Unless it was one of the Church's legendary heroes or top-ranked exorcists, none of them could even threaten Leo now.
And that was before he'd grown stronger.
Now, his demonic power had surged, his wings had grown from two to six, and on top of that, his newly awakened Sacred Gear—Zenith Tempest—made him far beyond anything stationed in Chiba Prefecture.
"Here, take this too."
Leo handed her another small device. "It's a scanner used to detect potential clients. Think of it like a radar—it pinpoints humans who might resonate with us. Just follow the directions it gives you and drop flyers at those locations."
After finishing his explanation, Leo sent Yukino off.
Though a little anxious, she didn't want Leo to see her as weak. So she took a deep breath, unfurled her devil wings, and soared out of the manor into the night.
Leo watched her go, then turned back toward the underground training room.
With a soft whoosh, six black wings spread wide behind him as he rose into the air once more.
It was time to train his control over the Sacred Gear.
"Fire!"
At his command, roaring flames exploded outward. Waves of heat surged like a crimson avalanche, engulfing the entire chamber in an inferno.
"Water!"
The next instant, vapor condensed out of thin air. A torrential flood cascaded down, sweeping across the scorched floor and extinguishing the fire, leaving behind a vast pool.
"Ice!"
Snowflakes began to fall. Bitter cold swept through the room as a freezing blizzard howled, and within seconds, the flood solidified into glittering ice. The sharp cracking of freezing water echoed through the underground chamber.
"Lightning!"
Leo raised his hand like a king commanding the heavens. Power surged through his body, shaking the ceiling as dark clouds formed overhead.
Thunder rumbled. Blinding bolts of lightning crashed down, shattering the ice and ravaging the entire arena.
It looked like the end of the world compressed into a single room. Even the magic barrier around the chamber flickered, barely holding together under the onslaught.
Moments later, Leo summoned fierce winds. Tornadoes ripped through the space, scattering stone debris and clouds of dust into a roaring storm that tore at the walls like a natural disaster made flesh.
"So this is the power of Zenith Tempest—the Sacred Gear ranked second only to the legendary Holy Spear, huh?"
He gazed at the wrecked training room in awe.
Controlling the elements—earth, water, wind, and fire—wasn't unheard of among beings with supernatural power.
Even he could replicate such phenomena with enough demonic power. But the results had always been weaker than energy blasts or light beams formed from condensed power.
This, however, was different.
Even among those skilled at manipulating elements, none could unleash destruction like this.
Because Zenith Tempest didn't just control the elements—it interfered with the natural world itself. It bent nature's laws to the wielder's will.
It ruled the sky, commanded the weather. Its essence wasn't mere elemental magic—it was dominion over creation itself.
That was why it ranked second among all Longinuss, and one of only four capable of erasing entire nations or reshaping the world's balance.
"Even though my Zenith Tempest just awakened, in terms of raw power… even an Ultimate-Class Devil would have to take me seriously."
Shock gave way to exhilaration.
"As I thought," he murmured, smiling. "Making Yukino my servant wasn't just about boosting my demonic power or rising in rank—it awakened this Sacred Gear."
His newfound strength and higher class had elevated him among High-Class Devils—but Zenith Tempest had given him something far greater: the ability to challenge beings above his league.
He clenched his fists, eyes burning with ambition.
"If I can fully master Zenith Tempest... I'll have enough power to threaten even Ultimate-Class Devils."
And that was just the beginning.
Sacred Gears were limitless. They evolved with their owner's will—growing stronger as their emotions and resolve deepened.
When a wielder's feelings became strong enough to defy the flow of the world—when joy, sorrow, rage, and desire all fused into one transcendent intent—the Sacred Gear would reach its ultimate state: Balance Breakers.
That was the realm of forbidden power, capable of shaking the world's equilibrium.
Once he reached that point, Leo would stand shoulder to shoulder with the Maou themselves—one of the strongest beings in existence.
That was the true terror—and the true promise—of a Longinus.
A weapon powerful enough to destroy gods and Maou was no myth.
From the moment Zenith Tempest awakened, Leo knew it.
His future no longer depended on his status as a devil—
but on the might of the world's second-strongest Longinus.
"I'll master Zenith Tempest as fast as I can," he vowed quietly, eyes gleaming. "Only then will I be able to glimpse the realm of Balance Breaker."
With that resolve blazing in his chest, Leo unleashed his Sacred Gear once more.
Thunder roared. Flames and storm winds raged.
And in the depths of the underground chamber, the end of the world was reborn again and again.