Starting from Zero to Build a Demon Family
Chapter 21 - Mr. Demon, Can You Save the World?

Chapter 21: Mr. Demon, Can You Save the World?

Fujimi Academy.

Saeko, wielding her newly acquired katana, cleanly decapitated a zombie.

“What has this world turned into?” She flicked the blood from her blade and held it horizontally in front of her. Its polished surface caught her deep blue eyes and the sluggish undead staggering closer from behind.

“Teacher Shizuka, duck.”

“Huh?” The voluptuous blonde blinked, slightly dazed, but her body moved before her mind caught up.

Whoosh—

Saeko moved without hesitation. Her blade shimmered coldly as it cut through the air in a perfect arc.

Bang! Bang! Bang!

Three zombies dropped lifelessly to the ground, unable to resist in the slightest.

“Wow! Saeko, you’re amazing!” Shizuka crouched low, eyes sparkling as she clapped softly in admiration.

Saeko cast her a helpless look, then brought a finger to her lips to signal for silence.

Shizuka immediately covered her mouth with both hands and stared at her with wide, earnest eyes.

“You can get up now, Shizuka-sensei.”

“Mm-hmm!” She nodded rapidly, grabbed the medical kit she’d brought from the infirmary, and hurried after Saeko.

As Saeko cleared the hallway of lingering zombies, her mind churned. These creatures weren’t difficult to dispatch—but there were far too many of them.

She glanced out the corridor window, her gaze sweeping the school grounds.

A dense tide of the undead surged toward the building, their numbers overwhelming. Judging by the scene, the first floor was likely already overrun.

Saeko’s grip on the katana tightened, her knuckles paling. For all her mastery in swordsmanship, she was still human—she could tire, could bleed. The dead didn’t abide by such limitations.

This school wasn’t a place to linger. But—

“How are we supposed to escape?”

She stared at the horde stretching beyond sight, a tide of rot and death, and felt despair begin to stir. But to sit and wait for death? That wasn’t the way of the Busujima women.

“Shizuka-sensei, are you ready to push forward, even if it means dying?” she asked quietly.

“Um…” Shizuka touched a finger to her lower lip, then her eyes suddenly lit up, as if recalling something. She reached into her cleavage.

“Ah, found it!”

She pulled out a black parchment that radiated a vaguely ominous energy.

“Why don’t we ask the demon for help?”

She offered the parchment to Saeko like a child presenting a treasured toy, her eyes full of hope.

Saeko stared wordlessly. This was her fault for expecting something useful from this airheaded teacher. But confronted with that hopeful gaze, she sighed and took the paper in silence.

Demon Contract Summoning Scroll.

It certainly looked the part. Saeko raised an eyebrow.

“Hehe.” Shizuka gave a mischievous smile. “Don’t underestimate it, Saeko. That parchment showed up in the infirmary out of nowhere. Every time I tried to throw it away, it reappeared in the same place.”

“Even fire couldn’t burn it!”

“It must be a demon’s prank!”

She looked utterly convinced.

Couldn’t it just be a student prank?

Saeko almost voiced the thought, but Shizuka was already handing her a pen.

She glanced down at the swaying chest from which the item had emerged and muttered, “Is that some kind of dimensional pocket?”

Forget it. Might as well humor her.

Saeko took the pen and scribbled her name where it said “Contractor’s Signature.”

“Alright, pretend play—”

Before she could finish, a flash of brilliant light flared in the hallway.

Buzz—

A dark, arcane magic circle surged to life beneath her feet, inscribed with symbols that defied understanding.

Her pupils contracted sharply as she instinctively gripped her sword tighter.

Click!

Footsteps echoed down the hall.

“Are you my contractor?”

Saeko looked up.

A boy with black hair, crimson eyes, and an aura of regal indifference stood before her.

Lynn.

“Is he really… a demon?” she murmured, disbelief tightening her voice.

But that summoning circle wasn’t her imagination.

Rip—

Black wings tore through the fabric of the Shuchiin Academy uniform, spreading from his back in an elegant arc.

“Authentic.”

Saeko’s breath caught, her pupils dilating. She opened her mouth, but the words didn’t come.

Clap!

Lynn’s demon wing snapped outward, batting away a sneaky hand.

“Oww, that hurts!” Shizuka crouched behind him, puffing air onto her stinging hand like a child trying to soothe a burn.

Saeko’s nerves twitched. She took a slow breath. “Shizuka-sensei… what were you doing?”

“Eh-heh-heh.” Shizuka gave a sheepish giggle. “I wanted to touch them to see if they were real.”

Can you at least show the demon some basic respect? What if he really turns this world into a living hell?

Then again… wasn’t the world already a living hell? Or rather, this world?

As Saeko and Shizuka exchanged words, Lynn stood silently, lost in thought. The moment he laid eyes on Saeko Busujima, he knew exactly where he was. One of the classic low-level starter worlds for transmigrators. Predictable, even cliché.

But for him—and more importantly, for his followers—this world had its merits. A perfect place to grind for experience. Especially when his familiars were still under-leveled.

Lately, he’d been pondering the best leveling spots for Kasumigaoka Utaha and Yotsuya Miko.

In a modern human society, there were far too many restrictions. Curses were everywhere, sure—but they usually gathered in crowded places.

To avoid drawing attention, they had to wait until nightfall.

Such inefficiency. But this cross-world summoning solved that problem.

A world overrun with undead? It was practically a natural low-level XP farm…

In addition, this world also had beings with the potential to become followers.

Lynn glanced at the flashing Demon Pawn skill on his panel. He had a feeling that recruiting familiars in this world would be far easier than in his own.

“So.”

Lynn fixed his gaze on Saeko Busujima, a faint, unreadable smile tugging at the corners of his lips.

“Contractor, what is your request?”

Saeko drew a long breath.

That this piece of parchment had truly summoned a demon was… outside anything she had expected.

Her worldview teetered slightly, as if a core pillar had been knocked off balance. After all, who would’ve imagined that demons truly existed?

But in a world that had suddenly become this unrecognizable, maybe the appearance of a demon made some kind of sense.

Anyway, the demon was already here. Might as well try.

Saeko’s eyes flickered with indecision, then steadied. She spoke slowly, cautiously, as if afraid the wrong words might trigger disaster.

“Um… Mr. Demon. Can I ask you… to save the world?”