After a while, Shion and Luna both wore deeply satisfied expressions.
"Haa… That was the best…"
"Yes… It's really addictive…"
At their feet—no, floating in the air—Sakura Mochi hung its head limply, breathing heavily.
"Why do I have to go through this…"
Oliver gave a wry smile and shrugged.
"…Tough break, huh."
"To think the day would come when a human would pity me…"
Sakura Mochi muttered in a frail voice, staring off into the distance with a faraway look.
In the somewhat calmer atmosphere, I asked again.
"…So, what exactly is this guy?"
Fuuka answered without hesitation.
"It's the materialized consciousness that resided in White Cherry Blossom. It started appearing after I formed a cooperative relationship with it. You could call it the very embodiment of youkai power. That's why it can answer Orun's earlier question."
"I see…"
I nodded with a serious expression and shifted my gaze to Sakura Mochi.
"Then let me ask again. What exactly is youkai power?"
"Hah? Why do I have to explain it?"
The fox immediately turned its face away and let out an annoyed huff.
The moment it did, Fuuka's eyes narrowed slightly.
"Sakura Mochi. Don't be mean."
Her voice was gentle, yet it carried an undeniable pressure that left no room for refusal.
The fox's shoulders twitched. After a short silence, it let out a small sigh.
"Tch… Fine. I just have to explain it, right…? …Damn, explaining stuff to humans… I really have fallen low."
Sakura Mochi snorted in dissatisfaction, then straightened its posture while still floating in the air.
Its ears and tail swayed gently, and its voice took on a surprisingly intellectual tone that contrasted sharply with its earlier pitiful state.
"So, you wanted to know about youkai power?"
"Yeah. I'm counting on you."
Sakura Mochi exhaled once before beginning.
"First of all, youkai power is a force born from feeding on the 'negative emotions' that dwell within living beings. Anger, hatred, jealousy, fear. These dark emotions are far more intense than ki, which feeds on 'positive emotions.' They swell up like fire consuming firewood and can even turn the host themselves into a monster."
The fox drifted lightly through the air as it fixed me with a sharp gaze.
"And humans let go of it. The reason is simple. It was too strong. Too many people lost control and ended up destroying themselves and their comrades. Over thousands of years, they carved a mechanism into their genes to suppress youkai power. In other words, humans discarded it as 'a power they couldn't handle.'"
There was a sarcastic edge to its final words.
"However, only humans discarded it. Other creatures still possess it. And occasionally, some get consumed by it and turn into monsters. Humans call those 'youkai,' and specific clans like the Shinonome family have been exorcising them for many years."
"Youkai… I know they exist from old documents, but I've never actually seen one. Are they that rare?"
"They're definitely rare, but the reason you've never seen one is different."
"Different?"
"This world itself is designed so that youkai cannot be born. That's all there is to it."
"The world… So the principles are suppressing the youkai power in other animals as well."
"Exactly. …Anyway, we got off track. In short, youkai power is the opposite of ki, but at its root, it's the same… a 'power that flows within living beings.'"
At Sakura Mochi's words, I furrowed my brows.
"So, in the distant past, humans could handle both ki and youkai power. But over a long time, by discarding youkai power, they even lost the ability to manipulate ki?"
"You catch on quick."
The fox swayed its pale cherry-blossom tail as it continued matter-of-factly.
"Because they sealed away youkai power, the circulation of ki also grew sluggish. That's why humans forgot how to manipulate 'the power within themselves' and became clever little creatures who rely on wits instead."
"…But according to the documents, people who could use ki started appearing again in the age of fairy tales. Why is that?"
At my question, the fox narrowed its eyes while drifting through the air.
"Probably because a new power called 'magic power' appeared. It wasn't something you're born with—it's energy that fills the environment. That stimulated what was sleeping inside humans."
"Stimulated…?"
"Yeah. Once magic power filled the world, the ki sleeping inside humans began to awaken in response. Because magic power and ki are in a mutually antagonistic relationship. Yang and yin—when one grows stronger, the other inevitably wakes up as well."
I placed a hand on my chin and slowly searched for the right words.
"…If ki and magic power are antagonistic, then youkai power, which is the opposite of ki, would be in a mutually generative relationship with magic power, right?"
"Exactly. In theory, that's correct."
Sakura Mochi lifted the corners of its mouth in a sardonic smile.
"That said, it's still far too much for humans to handle."
Reaching the core of youkai power, I felt something click into place deep in my chest.
My ultimate technique—[Final Form: Mont Ende].
Its essence was to push both ki and magic power to their absolute limits and intentionally make them clash.
It raised physical ability to the maximum while generating a force capable of annihilating all things through that clash.
But that was equivalent to using the pinnacle of ki—[Demon Break].
[Demon Break] was a power that erased magic power, and it carried the danger of potentially destroying even my own body, which had become attuned to magic power through my special ability.
(But what if—I were to insert youkai power between the two?)
The backlash caused by the clash could be softened by using youkai power as a "buffer."
Instead of ki and magic power devouring each other as they circulated through my body, they could maintain balance by using youkai power as a medium.
If that were possible—then a version of [Final Form: Mont Ende] that did not damage myself could be achieved.
I quietly exhaled.
"…So youkai power really was the final piece."
At my murmur, Sakura Mochi, who had been floating lightly in the air, twitched its ears.
"Hey, you're not seriously thinking you can handle youkai power, are you? I already told you. Youkai power is something humans cannot handle. It's carved into your genes."
The fox's voice was cold, and its tail swayed restlessly.
"You say that, but Fuuka can handle it, right? Then there must be a way."
When I countered, Sakura Mochi fell silent for a moment.
Its ears perked up, and it shot a sharp look at Fuuka.
"I don't want to admit it, but this little girl—"
"—Fuuka."
Fuuka quietly corrected the fox's way of addressing her.
".... ...Fuuka is special."
Reluctantly correcting itself, Sakura Mochi continued.
"She is a direct descendant of the Shinonome. A clan that has continued to exorcise youkai—monsters consumed by youkai power—for generations. On top of that, she has synchronized with me, White Cherry Blossom, the only youkai power whose existence is recognized in this world. With all those conditions met, Fuuka can finally handle youkai power."
After stating it plainly, Sakura Mochi lifted the corners of its mouth in a mocking grin.
"Well, even Fuuka was scared of being swallowed by youkai power until very recently and could only handle a tiny amount of it."
Its tail swayed from side to side as it narrowed its eyes teasingly.
"You don't have to say unnecessary things."
Fuuka frowned and cut in.
"…So the biggest obstacle to handling youkai power is the genetic mechanism in humans that suppresses it, right?"
"…? Yeah, that's correct."
Sakura Mochi snorted lightly, as if to say "Why are you asking something so obvious?" and swayed its tail.
"I already had some ideas about that part, so it shouldn't be a problem. In fact, it might even work in my favor… The real issue is how to learn the sensation of manipulating youkai power itself. Hey, Sakura Mochi, do you have any ideas on how to learn that sensation?"
"Wait, why are you also calling me by that fluffy name—hold on! Why are you already assuming you can do it!? This isn't something an individual can just figure out on their own!"
At Sakura Mochi's panicked protest, Fuuka shrugged her shoulders slightly.
"Just like I'm special, Orun is also special in a different way. Orun has the special ability called [All Things in Creation]. It lets him use any power he has seen or heard."
"Hah? What the hell is that?"
Sakura Mochi openly showed a stunned expression.
"It's not as simple as being able to use something just by seeing or hearing it. That said, this time I'm planning to try learning it through a different method than [All Things in Creation]."
"…Really?"
"Yeah. Well, I'll talk about that later. I haven't reached the point of being certain I can do it yet. —Anyway, going back, do you have any ideas on a method?"
"…The quickest way would be to synchronize with me, White Cherry Blossom. But that's absolutely impossible. No matter what ridiculous ability you have, synchronization requires bloodline."
At those words, I couldn't help but frown.
(Bloodline… Similar principle to how special abilities are inherited. Then, by broadly interpreting my special ability… No, that might be difficult… Besides, White Cherry Blossom is Fuuka's precious blade. I have no intention of borrowing it. So that's out. In that case—)
"—No, there was one more…"
As I was thinking, Sakura Mochi spoke as if it had just remembered something.
"One more? You mean there's another demon blade?"
"Yeah. Well, it's a cheap knockoff compared to me, but there's no doubt it carried youkai power."
"Where did you see it?"
"It was the sword carried by the man Fuuka exorcised."
At the casually spoken words, Fuuka blinked repeatedly.
"I exorcised?"
"There was one, right? The crude man Fuuka cut down at the bottom of the big hole Orun opened."
"...?"
Fuuka still didn't seem to get it and tilted her head.
But since it mentioned me opening a big hole, it must have been an enemy we fought together.
There weren't that many battles where Fuuka and I fought side by side.
Among those, if I opened a big hole…
"—The "Battle Ogre"."
One of the executives of the "Cyclamen Cult", the "Battle Ogre" Dimon Ogle.
When I fought the "Rakshasa" Stieg, I left the "Battle Ogre" to Fuuka.
The "Battle Ogre" had used a greatsword. So that sword had carried youkai power.
"…Now that you mention it, he was using a copper-red sword. If it's that sword, I still have it after defeating the "Battle Ogre"."
Fuuka said that and took out the sword the "Battle Ogre" had used from her storage magic tool.
"I'll give it to Orun."
I accepted the sword with both hands.
It had a surprisingly solid weight in my palms.
"…Thank you, Fuuka. Thanks to you, I now know the path I should take from here."
First and foremost, I needed to help Luna become a transcendent and fulfill my promise with Titania.
And then, for me to learn how to handle youkai power.
I would definitely accomplish both.
Gripping the hilt to confirm its weight, I quietly renewed my resolve in my heart.