Prologue: Crew Captain, Backup Squad

In an apocalyptic world, it was hard to find hope when friends and family died with a visible cause.

A zombie incident happening once would be unfortunate, but the second one needed a justification from the governing power. How could they allow such things to happen in their presence?

The result would be tightening security and control.

Quarantines and prevention measures learned by every citizen regardless of who they were in status.

So many years have passed at this point that the prevention measures are now a way of life for them.

In the headquarters of the Harmonic Theory religious organisation, a lethargic man held his hand to the sky. However, his pale face and sickly appearance had yet to mire his handsome features.

On the back of his hand was metallic prevention measure that every child of this era had to be implanted with. Only his personal implantation looked far more majestic and golden in nature.

This called a 'Limiter'.

"Are you worried about something, Overseer Celest?"An emotionless voice had spoke kind words.

The religious leader, Celest Vagabond, turned to look at his longtime comrade that had been by his side for far too long. A pitiful woman who had become numb to her own feelings due to the passage of time.

"Why do birds fly?" Celest asked with meaning. It was a question the woman couldn't fathom.

"Is there a need to answer that?" She knew this man enjoyed these kind of conversations, but didn't feel the need to humour him every time. He had many conversation partners, so it didn't matter.

"My dearest old friend, please..." Celest's unresolved eyes showed he wasn't kidding this time.

The woman didn't know why it was so important...

...but since it came to this, she answered:

"You rarely give me that weak look. Fine... Birds fly because it's their role in life." She gave her opinion.

"Role...?" Celest found this intriguing.

"If birds didn't fly, humanity would never have desired to surpass them. They fulfilled their role in service of humanity." The woman gave such a bias answer, but the Overseer liked this kind of attitude.

She was being sincere...

"Then why do humans limit themselves despite desiring much more?" Celest made her notice her own Limiter. It was a shackle that bound humanity from reaching their full potential in the art of magic.

"Don't joke about this." Despite his high status, the woman didn't act like a subordinate whatsoever.

Celest raised his hands and gave up: "Fine. Sorry, sorry... Don't think of me as the bad guy for this."

Seeing her mood like this made the man sigh and think of the past. She used to smile a lot more often.

Now those moments are fleeting...

Was it the destruction of everything they knew dear that caused this? Or was it that incident from 500 years ago still haunting her? But even if it did, there was no good in having her life stuck in a loop.

The world didn't originally have 'Miasma' lingering in the air, but ever since the calamities from 50,000 years ago, the threat of being infected by Miasma and turning into a Nether Demon never faded.

It could only be warded.

And after the illness struck, the only option from there was either becoming a Demon or dying.

This was the apocalyptic world they lived in...

Humanity kept on flourishing, but Demons would always attack and take away the peace of the world.

It was why he had set up an Academy for exorcists in recent times. In fact, that wasn't his first attempt.

In city named 'Faustus', he had constantly improved the way exorcists hunted Demons every generation.

But never had he found any hope for humanity.

Demons grew stronger as humanity did, and the worst instances of that were the fall of 'Calamities'.

The female friend Celest had known for a long time had become crippled after fighting the recent one.

He too didn't come out unscathed the first time a Calamity came down and reaped 300,0000 souls.

Yet here he was, joking about how they were constantly fighting both illness and demonic threats.

"I have some good news for you." Celest got to the point of why he called her here at such a time.

"What's wrong?" The bland woman listened close.

But instead of hearing anything, a file was thrown in front of her. Containing details about a certain boy.

She flipped through and skimmed the pages, but became more interested to the point of reading it again. There was no way what she saw was true, but the expression on Celest's face told no lie.

"Why didn't you tell me about this?" The woman slammed the papers on the table and let it scatter.

The word 'Immune' appeared a lot on the paper.

"We found him washed up on the borders of our city without any memories. No, that isn't quite right." A strange expression appeared on Celest's face when he remembered the crazy things he personally heard.

"That wasn't my question." A blank face came closer.

"It looks like he has some Miasma Poisoning of some sort and believes he comes from a land 100,0000 years ago... Valkcry Empire." Celest held his breath after speaking these words with a tense expression.

This lost ancient empire... These words caused the woman's expression to flicker and take a step back.

The people who even remembered this ruined empire were probably only counted on one hand.

It was at a time before the Miasma. Before the calamities that almost wiped humanity off the Earth.

Moreover, he had an immunity to this poison...

"Have you done any tests?" She calmed down and wanted to hear the validity of what he had spoken.

"He seems normal physically, so I let him loose." A smile appeared on Celest's face while stopping her.

Then finished what he was saying with: "Unless you want me to lock him up forever. That fine with you?"

"Tsk..." She clicked her tongue.

They weren't heartless people. Living for so long didn't make them immune to human emotions.

And as an idealistic person, she believed locking up someone who did nothing wrong... was despicable.

"Then it's decided then. We have the time to sit back and observe. Although the two Eruptions earlier had mostly crippled our strength, we can rely on this new generation to save themselves. I believe in them." A strong air of majesty exuded out of the man's bones.

It was at that moment he truly seemed like the Overseer that watched over an entire religion.

Reason dictated that they mustn't let their feelings get in the way of nurturing the next generation.

'Reason' was also the basis of Harmonic Theory.

Celest, the Overseer watching this world, would continue to watch this strange youth's future actions.

For now, he kept his distance appropriately.

On an airship far from Faustus City, but still close enough to see the skyscrapers of the central district there, the individual on the file got ready. He put on his military uniform and put on his captain's hat.

He dressed spotlessly white, but didn't seem to really like having to wear this stuffy uniform all the time.

The youth tilted his head, then took off the extra layers until the sleeveless white shirt was left.

He looked built for someone his age... but that was all there was to him. Such a young man didn't fit the role he was given. Being in charge of an entire ship run by an AI and leader of a crew of strong exorcists.

The type of guy who would disregard appearances so long as no one above his rank saw him like this.

He stepped into an elevator and went up to the main cabin. A place combined with the control centre.

"Ryan Rayleigh reporting for duty!" He saluted to three young women who were waiting for him there.

Today would be a special occasion for them.