"Outside the world...? What do you mean?"
I felt more than a little bewildered.
The Great Spirit spoke of it as if it were a matter of course, yet it was a term I had never heard before.
While the mention of a supernatural existence piqued my interest, the conversation was jumping ahead so rapidly that I feared I would lose track of it entirely.
Meanwhile, the Great Spirit continued her explanation with clinical efficiency.
"Do you know what lies beyond the sky?"
"A void devoid of magic power, or so I have been taught."
I drew upon the knowledge I had acquired during my life as a human.
Long ago, a certain mage had attempted to ascend to the heavens. However, he ran out of magic power mid-flight and plummeted to his death.
The concentration of magic power in the atmosphere thins significantly once one passes a certain altitude. While this doesn't directly affect the maintenance of life, it causes magic to function poorly, making the activation of spells dangerously unstable.
Thus, no one has ever truly reached the edge of the sky.
Some scholars argued it was the Domain of the Gods. Given that it was physically unreachable by humans, that theory had gained a fair amount of traction.
Of course, I didn't believe such common superstitions, but I lacked the evidence to disprove them.
The Great Spirit seemed to know the truth.
"That is half-correct. There is certainly no magic power there, but it is no void. Beyond the sky lies the 'Outside the World'."
"So, the cause of my condition is an inhabitant of this 'Outside the World'?"
"Yes. And they intend to seize control of this world as well. We call these inhabitants the 'Beasts of the Outside World'."
"Beasts of the Outside World..." I muttered.
If the world's defense mechanisms used such a name, the situation must be quite advanced. This was a problem of a far greater scale than I had anticipated.
"There are multiple Beasts of the Outside World. While some appear to be in league with one another, they generally act alone. They are currently hiding themselves with great skill, but they will eventually reveal themselves."
"My spies have found nothing. If such entities existed, we would have discovered them by now."
"The enemy is a monster from outside the domain. There is no guarantee that the laws of this world apply to them. Surely you understand that by now."
I had no rebuttal for the Great Spirit’s point.
She was exactly right.
I hadn't been able to use my perception to detect these things, and as a result, I was currently plagued by a mysterious sickness. It was utterly pathetic. I was in no position to argue while my own failures were laid bare.
"I have reviewed Yura's memories; you made eye contact with a foreign spy, did you not?"
"So that was the source after all."
"Indeed. They had been turned into the Beast's Kin. By meeting their gaze, you were eroded. For the moment, it has only manifested as physical illness, but it will eventually reach a point beyond recovery."
I had vaguely suspected the Great Spirit’s warning.
I thought I had repelled any mental contamination, but it seemed the influence had taken root anyway. It had merely triggered with a delay.
Failing to see through it was a result of my own lack of experience. The enemy had used an ability that was not based on magic. Even so, as the Demon King, it was my responsibility to deal with it.
Admonishing myself for the oversight, I turned back to the Great Spirit.
"How do I fix this?"
"If you slay the beast that attempted to contact you, your condition should clear."
"I can't slay it if I don't know where it is."
The Great Spirit shook her head. She reached out and touched my cheek.
"Finding it is not my task. I believe you are capable of doing so on your own."
She stepped away from me. Looking out the window, she spoke in a voice devoid of emotion.
"The Beasts of the Outside World are appearing everywhere. My jurisdiction is limited to this continent, but I intend to have you assist with the culling."
"Fine. Leave it to me," I replied instantly.
The enemy was a supernatural existence. If they possessed enough power to inflict such a state on me, they were undoubtedly monsters.
Such beings had bared their fangs at the world. I could not let them roam free. If they were allowed to run rampant, my ideal—World Peace—would slip further from my grasp.
Fortunately, my goals aligned with the defense mechanisms. Knowing I could cooperate with them was incredibly reassuring.
"I will contact you again once your condition has improved. Please, make haste."
With those words, the Great Spirit's presence began to fade. Just as I thought she was gone, she spoke once more.
"There is one more thing I should mention."
"What is it?"
"The source of your suffering appears to be rooted within your spirit."
"My spirit..."
I turned her words over in my mind. Then, I expressed my gratitude.
"This is valuable information. It helps."
"I hope it provides a path to the solution."
With that final remark, the Great Spirit’s presence vanished completely.