Chapter 1: Unaware that it would become the greatest mistake of her life (1).

The realisation suddenly came to me when I was about five years old.

The trigger was the heroic tale of the warrior Lier. Lier was the legendary hero who defeated the Demon King and saved the continent 500 years ago. The moment I heard the name Sien Lenos, who was said to be his companion, a spark ignited in my mind.

“…Ah.”

This is me.

This is truly my name.

The flame of memory that had been lit spread like wildfire through the circuits of my mind. I recalled what kind of being I was, what I attempted, what I was capable of, and what I actually accomplished. And ultimately, what kind of end I met as a result.

“So, I’ve been resurrected.”

I don’t know how, but Sien had been brought back to life, crossing a span of 500 years. However, the reasons for his resurrection, or why it happened after 500 years, were not immediately important. What was more important was:

“Of all the places to be resurrected… this is not a good start.”

Sien clicked his tongue as he looked out the window.

The place where he resided was a slum, where the lower class gathered. It was the last festering spot in the otherwise splendid capital of the Holy Kingdom of Astaria. A dwelling place for the defeated and a sanctuary for underground organizations.

The largest slum in the Kingdom of Salem, Undercut.

It was there that Sien had been born.

“I wasn’t hoping for a grand start, but……this is  a bit too much, isn’t it?  At the very least, I would have preferred a middle-class environment.”

While it wasn’t unheard of to have lower-class citizens in this world, it was extremely rare to find a family so poor that they lived crammed together in a single, leaky shack. Yet, Sien had drawn the short straw, being born into one of those few unfortunate families.

“To make matters worse, this body is…”

He then looked over at the bucket filled with rainwater.

 Reflected on the water’s surface was a delicate and fragile-looking silver-haired girl. Even considering her young age, her thin arms looked doubtful to lift even a twig. But in contrast, her beauty was exceptional. Though she was grimy from not having bathed at all, even in that state, her beauty was enough to captivate those around her. With an innate, graceful dignity, she possessed a face that seemed like a gift from the heavens.

However, the expression on his (or her) face was filled with deep concern.

“If only the environment had been better, this beauty would have been an asset…”

Unfortunately, in a place with such poor security, a pretty face is more of a curse. Who knows when a drunken vagrant might grab her, violate her, and rob her of her purity?

No, that might even be the better outcome. If she’s really unlucky, she could be kidnapped by professional slave hunters and sold off. In that case, the only future awaiting her would be a lifetime in a hell she could never escape.

A frail body, a pretty face, and living in a slum—the synergy of these three elements was the worst possible combination. If she hadn’t awakened her memories from her previous life, she would have undoubtedly met a tragic end.

“Still, the fortunate thing is that it’s not too late.”

In the human body, the organ responsible for magic power stops developing naturally around the age of 8 to 10. This is why human nobles buy every powerful elixir they can find to have their children drink them before they reach their growth limit. The magic power established during this period influences the rest of their lives.

On the other hand, middle-class families that live day to day, or the lower-class citizens scraping by, can only dream of such elixirs. This is why the class system has persisted even 500 years later.

So what about Sien?

“Well, if I don’t have it, I’ll find another way.”

In truth, Sien’s origins as a demon weren’t particularly remarkable either. At best, he was of middle-to-low rank. The only reason he managed to rise to the position of Demon King from such an insignificant background was one thing: Sien was exceptionally clever and talented. He could still clearly remember techniques for rapidly gathering and storing magic power, even after 500 years.

“Of course, I was once the Demon King, after all.”

Sien said this with a smile as she lay down on the bed. Her biggest advantage right now was that she was a child—a sickly girl at that—so she wasn’t given many responsibilities and had plenty of free time. In other words, she had ample time for self-improvement.

So, the first priority was to regain her strength. Everything else could be dealt with later.

Three years later.

 Around her 8th birthday, Sien had regained about 30% of the power she had in her prime.

Though 30% might seem small, it was 30% of the power that once terrified the entire continent. At this point, her combat abilities far surpassed not only ordinary knights but even the captain of the royal guard. Of course, no one knew this except Sien himself.

Feeling confident that she could now protect herself, Sien decided to proceed with the second plan she had been keeping in her heart.

“Mom~ can I go to the central temple just once?”

“Hmm? Why the central temple?”

Sien’s current mother, Claudia, asked with a puzzled expression. Her daughter’s sudden and unusual request had caught her off guard. When Claudia turned to look at her, Sien, with a shy smile, twisted her fingers and replied,

“Well… I want to visit the place where the legendary hero Lier is said to be resting… You know, they have that huge statue of Lier there, right? And the holy sword Exia too!”

“…”

Seeing her daughter’s eyes sparkling with dreams and hope, Claudia’s face filled with concern.

“Well, Sion, the temple charges an entrance fee of 5 gold per person. Unfortunately, Mom doesn’t have that much money—”

“I have it! Here, 5 gold!”

“!?!”

Claudia was shocked at the sudden sight of the gold coins being held out to her.

“Where did you get that money?! Did you steal it from somewhere-“

“Oh, no way~ I found it on the street! A drunk man was walking down an alley and dropped it. It’s not really a crime, right?”

“But you should have returned it, dear…”

“I tried, but when I went after him, he was already gone. I didn’t know who he was.”

“Hmph…”

Claudia held her forehead in her hand, exasperated. It sounded like a lie, but there was no evidence to accuse her. And with her daughter smiling so innocently, it was even harder to press the issue.

The truth, however, was a different story—of course, it was a lie. The whole ‘I found it’ part was false. In reality, she had picked the man’s pocket, using magic to do it quietly. While it was one of the least impressive ways to use the powers of a Demon King, Sien didn’t mind. “Pride is a luxury,” was one of her guiding principles. Pride is fine when you have the luxury to afford it, but when you don’t, it can be a huge liability, one that causes significant losses.

Sien had never hesitated to humble herself when necessary. This was why she had been able to devise the bold strategy of joining the hero’s party even as the Demon King. And it’s also why she felt no shame in perfectly playing the role of an 8-year-old girl now.

Meanwhile, Claudia let out a groan as she looked at Sien.

“Alright. If you’ve already got the money, I guess there’s no choice. But you must come back before sunset, okay? And don’t be rude to anyone while you’re there.”

“Yay! Okay!”

Sien (now known as Sion in this life) cheered and jumped up and down in excitement. While this reaction was half an act, the other half was genuine. Sion was truly eager to visit the central temple. Not because it would offer her some benefit or opportunity, but for a deeply personal reason, unrelated to any calculation or strategy.

‘I suppose I should pay my respects at the place where you rest, at least once.’

The Hero Lier Riosoul—the most cherished friend of Sien Lenos in her previous life. Though he was long dead, it felt only right to offer him a flower, a gesture of respect. Sion had decided that once she regained her strength, this would be her first priority. She felt that nothing else could begin until she had resolved matters with Lier.

“I’m off then~”

“Hey! At least change your clothes before you go!”

Ignoring Claudia’s words, Sion ran out the door. It just so happened that the weather was perfect for an outing—a bright and sunny spring day.

The Temple of Ashtaria, located in the capital city, was a grand place. Although temples are typically seen as places of solemn prayer, this one was an exception, known more as a tourist attraction. Perhaps because pilgrims from all over the world flocked to it, the symbolic titles of “the place where the goddess delivered her oracle” and “the place where the hero rests” held great significance.

“That’s why even a poorly dressed girl can enter as long as she pays the fee.”

Sion smiled as she passed through the large marble entrance.

It wasn’t exactly a positive image for a temple to charge an entrance fee. She had even heard complaints that it was overly materialistic and focused on money. However, this was somewhat tolerated because the temple, as the headquarters of the Goddess Church, had immense financial responsibilities to manage.

“There are so many people in this world who think money just falls from the sky,” Sion thought, recalling her time as the Demon King. Both the demons she ruled and the hero’s party lacked a proper sense of financial management. Mostly, it was Lier’s fault for being too generous with money, always eager to help others.

Come to think of it, she had been the one who most often scolded Lier for such ‘wasteful’ spending.

Ah, fond memories.

“Ladies and gentlemen, if you look ahead, you’ll see the enormous statue of the hero. And below it, there’s a relatively small stone coffin. Inside that coffin rests the remains of Hero Lier. Of course, you mustn’t touch it.”

A nearby tour guide emphasized this point to the group. Sion, who had quietly joined the group, also looked at the coffin the guide was pointing to.

The plain, unadorned stone coffin was the kind you’d find anywhere. It was indeed a place where Lier could be resting.

“Even so, your achievements haven’t been forgotten. As your friend, that’s what pleases me most.”

Even though 500 years had passed, which should have given way to ruthless reevaluations, the name Lier Riosoul remained great and glorious. As Lier’s friend, this was what made Sion happiest.

After being lost in thought for a moment, Sion’s gaze shifted to the golden-hued greatsword embedded in the adjacent altar.

“Huh, that’s-“

“And now, if you look to your side, you’ll see the legendary holy sword, Exia, once wielded by the hero. It’s said that the goddess herself forged it, making it the greatest sword in existence! Only those chosen by the sword can lift it, which is why it’s called the ‘Sword of Selection.’ Is there anyone here who believes they are the next hero? If so, why not give it a try? You can test your strength for just 1 gold coin!”

The guide cheerfully announced the fee with a smile.

Taking money even here. Impressive. Sion was inwardly amused.

Meanwhile, a challenger had already appeared, striding confidently up the stairs. A burly, muscular man with a shaved head.

“Watch me pull this sword out in one go! Here we go! Hnnnnngh…! HHHNNNGGGHHH!”

The man gripped the sword’s hilt and strained with all his might. His face, and even his muscles, turned red with effort, but in stark contrast, the sword didn’t budge a single millimeter. It was as if it had been crafted directly into the altar from the start.

In the end, the man gave up and collapsed on the spot.

“Damn….! This thing is seriously heavy. Did you glue it down or something, priest?!”

“Haha, of course not! If you don’t believe me, feel free to check yourself!”

“Ugh…”

The bespectacled priest responded cheerfully, and the man scratched his head.

“If anyone could lift it, they wouldn’t leave it out here for everyone to see. Who knows if someone might try to steal it in the middle of the night?

The fact that this sword has stayed in a public place for 500 years without moving an inch is proof that it’s the real holy sword.”

“Yeah, I guess that makes sense…”

The man was convinced and descended the altar steps. He had never really intended to make a serious fuss about it.

“Hmm….”

Meanwhile, Sion, standing behind him, was deep in thought.

One gold coin. An amount that wasn’t particularly significant to her at the moment, but Sion didn’t like wasting money without a good reason. After all, she had seen that sword countless times in the past, and there was no need to pay just to touch it now.

“Wait a minute. That sword’s an Ego Sword.”

A sudden realization flashed through Sion’s mind. One of the unique aspects of the holy sword Exia was that it possessed its own consciousness. Although its playful and lively personality didn’t quite match the title of “holy sword,” it had gotten along well with Lier, who had a similarly upbeat nature. On the other hand, it often clashed with Sien, and their relationship wasn’t the best.

But now, that past tension didn’t matter much.

“Can I still talk to it, being an Ego Sword?”

For Sion, who had been feeling a strange sense of loneliness over the past three years, the realization that she might have someone to share memories of Lier with, even if that someone was a sword, was particularly special.

She couldn’t let this opportunity slip by. Sion quickly ran over and handed the priest a gold coin.

“I’d like to give it a try too.”

“Huh? Oh, so the little lady wants to try pulling out the holy sword?”

“Yes.”

Not that pulling it out was really the goal… Sion nodded anyway.

After all, that sword couldn’t be wielded by anyone but Lier. She figured she’d just pretend to put in some effort and use the chance to talk to Exia. Even though there was a long line behind her and she wouldn’t be able to talk for long, Sion climbed the stairs.

“Here we go.”

With her small body, even climbing each step was a struggle. Like a child, Sion had to take two steps at a time to barely make it up the stairs. The priest standing beside the sword watched Sion’s efforts with a fond smile.

“Need some help?”

“No, I’ve got it.”

Sion regretted not using transformation magic to increase her height.

“Okay, just grip the handle here and be careful not to touch the blade! Got it?”

“Yes.”

“Good. Now, just give it a good tug upwards! A strong tug!”

The priest mimicked pulling up with both hands, even adding sound effects like “tug! tug!”

Ignoring the priest’s exaggerated instructions, Sion used telepathy to communicate with Exia.

—“Hey, you dumb sword.”

“……….”

—“Are you sleeping? Wake up for a second.”

No response.

Sion clicked her tongue. For some reason, this sword always took forever to answer, even though it didn’t need to sleep. Why did it always seem to be dozing off? It was baffling.

“Are you trying, little lady?”

“Oh, yes.”

When Sion stood still, lost in thought, the priest beside her asked with a puzzled expression.

Her thoughts snapped back to reality.

“Just a moment…”

Since she wasn’t going to be able to pull it out anyway, she figured she might as well pretend to give it a real try. Sion gripped the sword tightly and tried to lift it.

Little did she know, this would be the single biggest mistake of her life.

“Here goes!”

She swore, she only used the slightest bit of strength. Even though she tried to put in some effort, at the end of the day, it was the strength of an eight-year-old girl.

However, that was enough.

—Shook.

The holy sword, which had remained immovable for 500 years, was suddenly pulled out as easily as one might pull out a radish. And in that instant…

“…….Huh?”

“……What?”

“……..?”

The priest who had been encouraging Sion from atop the pedestal, the guests waiting in line below, and the tourists who were busy looking at other sights—all of them turned their gazes toward Sion simultaneously.

What? What did I just see?

The holy sword had been drawn.

The holy sword… was drawn?

“…Huh? Wha—what??”

Sion was just as stunned as everyone else.

“Why, why did this come out? It’s supposed to be impossible for anyone but Lier to pull it out…”

Could it be that he was the chosen hero of this era?

No, that couldn’t be right. If that were the case, she wouldn’t still have her memories as the Demon Lord, and besides, the current world wasn’t exactly in a situation dire enough to need a hero.

As Sion’s mind raced, trying to make sense of the situation, a memory from her first year of adventuring suddenly resurfaced. It was from a time when they were still inexperienced rookies…

“Oh no! No no no!!! That ‘authorization setting’ from back then!!!”

Sion screamed loudly, completely forgetting that she was in a public place. Undoubtedly, it was the most shocking moment of her life, even including her past life