* * *

<"Uh...">

Jihwan thought for a moment. The question seemed to have caught him completely off guard.

<"... Was that sparkling effect when you turn book pages a trend?">

Hyeonyul then heard the sound of tapping.

"Isn't it a trend?"

<"Honestly, I don't know if it's a... trend. But I found an article saying it was popular. I don't know whether the article is genuine, but anyway, people must have found it fascinating.">

"It's unnecessary."

Having sparkles appear when you turned a page only hurt your eyes.

<"Things can become trends even when they're unnecessary.">

"Is that so?"

Hyeonyul thought he would never understand why this had become a trend, not even if he died and came back to life. How could something so inefficient become popular?

<"If you're curious, I can do it for you too. I'll try learning it.">

"That's not what I meant. Can that magic be used to start a fire?"

<"The magic that makes sparkles when you turn pages...?">

Jihwan reacted as though the question made no sense. Apparently, it would be difficult. If so, was this simply a trend?

<"Wait a moment, Bro. What mission are you on right now?">

"An amusement-park ride burned beyond recognition. Looking around, I saw magical formulas embedded in books. Even before entering this amusement park, I saw quite a few people with those books. I asked because I wondered whether there was a connection."

Hyeonyul briefly summarized his mission and mentioned what had seemed suspicious. In truth, that was all he had to go on for now. He had found nothing else yet.

<"They came to an amusement park, but brought... books?">

"Are they not allowed to?"

<"No, they can, but it's, um... I don't know if that many people would. People don't read as much as you'd think.">

"Is that so?"

<"Let me think about this for a moment, and I'll call you back. Is that all right?">

"Yes. Please do."

<"Hang in there, Bro.">

"Yes. Thank you."

After waiting for Jihwan to hang up first, Hyeonyul put his phone away.

'I'd better look around first.'

He had no choice but to inspect all the rides. Perhaps he would find something.

Hyeonyul raised his gaze slightly. The sun was out. Just as he seemed about to run forward, he slipped into a shadow without anyone noticing.

* * *

Hyeonyul searched as he traveled from shadow to shadow. All he found were belongings people had dropped, the disarray of the amusement park, and books bearing that magic, which had kept catching his eye. There were more than he expected, and he was beginning to find it strange.

He stopped paying attention to the park's unnecessarily grand, unnecessarily extravagant interior. He had no idea why they had drawn so many pointless lines on the outer walls.

'... There's nothing here?'

No matter how hard he looked, he could find no magical bombs at all. Beginning to question this, he emerged from a shadow.

「Absolutely Free.」

The words on a stall caught his attention. He looked to see what was free, and found the same books he had been seeing all along.

Hyeonyul studied the stacks of books still there. Their contents varied: comics, fairy tales, novels. There were countless different kinds, but all bore the same magic.

He tilted his head slightly.

'Free...'

He understood that things could be given away for promotional purposes. But there was no consistency here. They weren't promoting anyone, nor were these some author's new releases.

'There aren't even any coupons offering points on a website.'

They were simply giving them away at random. Hyeonyul scrutinized the stacks of books, then turned his head.

A woman dismounted from a creature that looked mechanical.

"Hello."

She bowed her head slightly, then pushed up her glasses. Seeing her sharply cut bangs and long, straight hair, Hyeonyul remembered having seen her somewhere before.

"I'm Chae Sujeong from Team One."

Sujeong introduced herself with a rather cold expression.

"Pleased to meet you."

"... Oh, are you the new recruit from Team Three who was there during the Poison King incident?"

"That's right."

Both Huijun and Sujeong remembered his voice. They must meet countless people. How was that possible? Still wondering, Hyeonyul looked at the mechanical creature.

"It's my power. I can make machines into my summons."

"In that case, do you have footage of what happened at the time?"

Sujeong briefly closed her eyes at his question, then opened them again. Usually, people asked what forms she could make, but this man was different. He saw straight through to what she could do.

"I do. It's horrifying. Will you be all right?"

"I'll be fine."

"One moment."

Sujeong reached toward her summon, and the face of the dog-shaped creature transformed into a screen.

"Have you met Kang Huijun?"

Sujeong asked before bringing up the footage.

"Yes."

"If he did anything to bother you, I'll apologize on his behalf."

"He did nothing of the sort, so there's no need to apologize."

He hadn't?

Sujeong immediately found his answer questionable. Looking vaguely troubled, she nodded a couple of times.

"Well, all right, then."

She tapped the screen, and the video began playing. A ride appeared on the screen, apparently captured by its security camera. People boarded the front and back of what looked like a long bench. Once everyone was aboard, the ride swayed left and right, then rose, stopped, and began spinning.

Perhaps a minute passed before flames suddenly engulfed it. There was no sound, but the people's movements suggested terrible agony. Before anyone outside could do anything, the flames swallowed everything. That was the end.

Sujeong glanced at Hyeonyul. His helmet concealed his expression. Only Team Three's new recruit wore such an unusual helmet.

"Are you all right?"

"Could you show me the moment just before the fire appeared?"

At his request, Sujeong swiped across the screen. The video rewound and stopped at the scene he wanted.

"Could you go back one second?"

Rather than answer, she rewound the video.

'Did he see something?'

Sujeong waited for him to speak. Without saying anything more, Hyeonyul turned his gaze toward the stacks of books.

"Please stand back for a moment."

"... Pardon?"

"There's something I need to check."

Hyeonyul spoke again, warning Sujeong.

He had confirmed several things from the footage. The fire had started not on the ride, but in the place where people left their belongings before boarding. Hyeonyul picked up a book and opened it, keeping his distance.

"... What are you doing?"

Sujeong couldn't help asking.

"You'll see."

With that simple answer, Hyeonyul rapidly flipped through the pages as he had seen in the footage. As the sparkling light intensified, he saw the magical formula change.

WHOOOSH!

At the same moment, the nearby books ignited, and flames surged toward Hyeonyul.

"Look out..."

"I'm fine."

Hearing his voice nearby, Sujeong turned her head. Her eyes widened; she hadn't noticed him coming over.

'... Just as I thought.'

Hyeonyul narrowed his eyes at the fire.

In the footage, someone had opened a book while holding a camera. They appeared to be a livestreamer. He didn't know whether it was part of a challenge, but as the wind blew in every direction and sent the pages fluttering wildly, he had seen the magical formula change just as it had moments ago. That magic had also appeared in the storage compartments.

Flames upon the target.

With those words inscribed in it, the magic had triggered a chain reaction.

"It isn't a magical bomb. These books are the problem."

"What...?"

"What I mean is..."

Hyeonyul broke off his explanation to Sujeong and took out his phone.

BZZZZ.

Senior Ye Jihwan.

It was Jihwan.

"Excuse me a moment."

After asking Sujeong's understanding, Hyeonyul answered.

<"Hello? Bro, can you talk?">

"Yes."

Hyeonyul switched to speakerphone so Sujeong could hear as well. He might not understand the explanation himself.

<"Earlier, you asked whether the magic that makes sparkles when you turn pages could start a fire.">

"I did."

<"In theory, it's possible. This isn't a spell being cast directly; the object has been enchanted with magic, right? In other words, magic has been imbued into it.">

"That's right."

<"When you enchant something, you can put two layers of magic into it. So theoretically, it's possible for the second spell to activate after the first enchantment is used. In practice, though, it's extremely difficult.">

"In what way?"

<"Just using the first spell consumes the mana needed for the second, leaving too little. Think of it as spent firewood. But it's still wood, so it can still burn, right? If you have a whole lot of that wood, you can produce a burst of flame as strong as fresh firewood would. You could use batteries or something else as an analogy too.">

Hyeonyul listened calmly to Jihwan's explanation. It was like scraping together the residual charge from countless drained batteries to fill a single battery. But even gathering it all would only fill one. He didn't understand what made that one capable of activating several at once.

<"But magic is different from firewood or batteries. It has continuity. So it's like bombs. If the same magic is nearby, one goes off and sets the others off with it. Does that... make sense? Magic is a little complicated.">

"... Ah."

Hyeonyul understood. In short, all the books he had seen were bombs, and turning their pages was itself the spark.

"Then is the sparkling magic itself a decoy to conceal the second spell?"

<"Exactly! You could think of it as camouflage for the second spell. But to do this, you first need permission from the Empire. They're really strict about it. And you need lots of enchanted objects. An enormous number. So...">

Jihwan faltered mid-explanation.

<"I-is that why you asked whether it was a trend?">

"Yes. That's why I asked."

<"... Then that article I saw earlier—was it written because this really had become a trend? Or was it something villains fabricated?">

"They fabricated it," Sujeong answered.

<"Oh, hello. How did they fabricate it?">

Jihwan responded naturally, unfazed by the unexpected voice.

'How does he do that...?'

Hyeonyul stared at his phone. What did one have to do to respond that smoothly?

"Sorry to interrupt, but the moment I heard that, I told my summon to search social media. The results confirm it was fabricated."

Sujeong spoke as she stroked her summon. Its face had returned to normal, and it was acting affectionately toward her.

"Most of the advertisements and videos posing as genuine reviews appear to originate from the same IP address. It was clearly the work of a coordinated operation. Team Leader Ye Juhyeon of Team Seven will investigate that more thoroughly than I can. I'll inform my team leader right away."

"Thank you for acting so quickly."

After thanking Sujeong, Hyeonyul addressed Jihwan.

"Thank you for the information."

<"Not at all. I'm glad I could help. But, Bro.">

"Yes?"

<"I mentioned that magic has continuity, right?">

"You did."

<"There's also a range limit. You need another spell to extend that range. Could you check whether that's there too... W-wait! I'll call you later! I'm on a mission too!">

Jihwan hurriedly hung up.

'So there could be another spell hidden here?'

Hyeonyul felt he had learned a great deal. This was information he hadn't known before.

In any case, now that he had identified the cause, he looked at Sujeong to continue the mission. Apparently finished with her call, she looked at him as well.

"As you heard from my teammate, those books are the cause. We should destroy every one we find. There were people outside with them too. And there seems to be a spell that extends the continuity of the magic."

There were three tasks to perform.

Destroy the books inside the rides.

Destroy the books outside the rides.

Destroy the magic that maintained the chain reaction.

"I think the last task would be best left to you, as Team Three's new recruit," Sujeong suggested.

He seemed able to see magical formulas, after all.

"Don't worry about the first two. Team One will make sure every last book is destroyed."

She smiled confidently and pushed up her glasses.

* * *

Hyeonyul slipped into the shadows and searched not only beneath the rides but above them as well. He didn't forget to destroy every book he saw. There was nothing difficult about it: destroying an enchanted object also destroyed its magic.

'?'

As he passed the Ferris wheel, Hyeonyul stopped in place. He had passed it several times earlier and seen all the lines drawn on it. Before, he had dismissed them as pointless decorations on its exterior, like those elsewhere. But when he moved closer, he sensed power.

'They contained mana?'

He followed the lines with his eyes. He couldn't see all the way to the top of the Ferris wheel, but they seemed to wind around it. The lines continued along the road and onto the outer walls of other rides.

'They weren't drawn just to make the place look extravagant.'

Hyeonyul ran along the lines. They extended beyond the amusement park, connecting to the lake behind it. What on earth were they?

He stopped before the lake. He sensed enormous magic within it.

'What is this...?'

He approached the lake and looked down. The formula was too vast to read, making it look like some strange spell.

'What kind of magic is this?'

Hyeonyul was about to use his shadow to rise higher when he hesitated.

["Nayun and Hyeonyul, you're both on support assignments, but you're needed in different places. Suspicious magic has been discovered. Nayun, your mission is to protect the White Sparrows searching for it."]

He suddenly remembered Nayun's assignment.

Surely not.