After healing from the aftermath of my actions, I didn't have the luxury of resting. There was too much to do, and too little time. One of the first things on my list was teaching Rachel, Cecilia, and Seraphina how to form their own True Domains.
Thankfully, Art had already handed me a blueprint for each of them, detailing how their respective Gifts could be harnessed to create a True Domain. All three of them were already at Immortal-rank, so the foundation was there—it would just take a few months of rigorous training. But when they succeeded, their strength would skyrocket, reshaping their abilities into something that could tip the scales in battle.
I thought back to my fight with Valen Ashbluff, the Necrotic Sovereign. My own True Domain, Divine Emperor's Throne, had made the battle one-sided. It wasn't arrogance—it was fact. Inside my True Domain, I didn't just fight; I dominated. That level of superiority wasn't something they'd be able to replicate entirely. My True Domain was special, relying on the harmonization of my three Gifts—a feat only I could achieve. Even so, their True Domains would be formidable, and humanity needed all the strength it could get.
The harsh truth was that humanity as a whole needed to level up. The demons were on a completely different playing field. Radiant-rank humans, the strongest we had, would be crushed by Demon Dukes. Art's warnings weren't exaggerations. My own battle with Valen, someone at mid Radiant-rank, proved that. Despite being at peak Immortal-rank, I defeated him without using my full strength—and still had enough mana left to rewrite reality and save Rin with Mythweaver. Valen, the strongest human in a fight, had been no challenge for me. The thought was sobering.
If humanity wanted to stand a chance, mind metamorphosis was the answer. It was the gateway to creating True Domains and bridging the gap with the demons. But mind metamorphosis required an anchor—a stabilizing force to support the transformation. That was the problem. I had already anchored the three girls, connecting their souls to mine. My soul was strong, but it wasn't infinite. Adding more anchors would overload me and kill us all. Worse, because their souls were connected to mine, they couldn't anchor anyone else either. A fraction of the strain would still pass through me, and the result would be the same.
We had six years. Six years before the pact broke and the demons invaded Earth in earnest. It wasn't much time. The current Radiant-rankers would be instrumental in the war, but they needed to grow. Fast.
And it wasn't just them. I needed to get stronger too. Radiant-rank. Divine-rank. Those weren't just milestones; they were necessities. The enemies we faced weren't just powerful. They were legends.
Alyssara Velcroix. Demon Lords. The Demon Overlord.
Their names loomed in my mind like mountains. Insurmountable. Distant. And yet, I couldn't stop myself from reaching for them. I wasn't strong enough to face them now, but I would be. I had no choice. Because if humanity couldn't close the gap, then our extinction was a certainty.
I closed my eyes, thinking of the path ahead. It would be brutal. It would be relentless. But I had no intention of failing. Not when there were still people to protect, bonds to strengthen, and a future worth fighting for.
Radiant-rank. Divine-rank. Whatever it took, I would climb. And when I reached the top, I'd make sure humanity climbed with me.
I looked at Rin, sitting close to me, her smile as bright and unburdened as sunlight breaking through storm clouds. The three girls were training on their own—no doubt determined to master their True Domains—but for now, it was just Rin and me. The quiet between us was companionable, the kind that didn't demand filling.
She was stronger now. There was no denying it. Splitting her Gift of Duality hadn't weakened her in the slightest. In fact, with her rationality restored, her strength had only grown. She wielded both her mana and black mana with a precision and harmony that was terrifyingly effective.
If we were to face off again, without my True Domain, I wasn't certain I'd win.
'She truly is strong,' I thought, watching her as she spoke animatedly, her dark eyes alight with a gleam of excitement I hadn't seen before. Strength tempered with clarity—Rin was an entirely different force now.
What truly struck me, though, was the sheer absurdity of her natural growth. While she'd been sealed away, time hadn't stood still for her. She had continued to grow, her mana core strengthening, her instincts sharpening. Even without formal instruction, she had reached a level of power that defied explanation.
"Father's going to start teaching me nine-circle spells," Rin said, her voice brimming with glee. "It'll take more time to master, but it's better this way. I'll reach Radiant-rank like a human."
I nodded, her words sinking in. If she stayed on her path, there was no doubt she'd reach Radiant-rank eventually—though the truth was, Rin didn't need nine-circle magic to progress. She could likely advance without it, simply by virtue of her unparalleled instincts.
'Wait,' I thought, my gaze narrowing slightly. 'Isn't she too much of a goddamn cheat code?'
The thought lingered as I considered her unique abilities. To break through major mana ranks required more than just raw power; it demanded enlightenment. Swordsmen, for instance, had to form a Sword Heart to reach Ascendant-rank, expand that into a Sword Domain to reach Immortal-rank, and finally achieve Sword Unity to break into Radiant-rank. Spellcasters, meanwhile, followed the standardized spellcasting model: seven-circle spells for Ascendant-rank, eight-circle spells for Immortal-rank, and nine-circle spells for Radiant-rank.
But Rin? Rin broke every rule.
She could cast spells instinctively, like a beast, bypassing the need for structured learning entirely. At the same time, she could advance through the mana core method—a system designed to require deep thought and deliberate cultivation. Somehow, she managed to balance instinct with intellect, growth with control. Her sheer versatility allowed her to grow at a pace that bordered on the absurd.
If she continued on this trajectory, she might surpass Lucifer's pace entirely.
'Truly, the Third Calamity,' I thought, my chest tightening with a mixture of awe and incredulity. 'The greatest genius this world has ever seen.'
I remembered reading the author's words in the original novel, how they had once mentioned that if not for Rin's circumstances, Lucifer wouldn't have held the title of the world's greatest genius. That crown would have gone to her.
And sitting here now, watching her, I couldn't disagree. Without mind metamorphosis, without the support most humans needed, she was already this terrifyingly powerful.
My heart thudded in my chest as the realization settled in.
More than Rachel, Cecilia, or Seraphina… Rin could keep up with me completely.
I found myself smiling. Not out of intimidation or fear, but out of relief. Of all the people I had helped, of all the allies I had gained, Rin might be the one who could truly stand beside me, stride for stride.
It wasn't a bad thing. No, it was a good thing. A very good thing.
I leaned back slightly, listening to her voice as she continued talking about her father's plans for her training. For the first time in a while, I let myself relax. With Rin, the path forward felt just a little less daunting.
"I'll teach you how to form a True Domain," I decided, my gaze steady as I looked at Rin. The words felt natural, almost inevitable. She had the talent—absurd levels of it—and now she had clarity. All she needed was direction.
"True Domain?" Rin tilted her head slightly, her dark eyes narrowing in thought. "You mean that golden throne room you used to… well, beat me?"
"Yes," I nodded, a faint smile tugging at my lips. "That 'golden throne room.' When you form your True Domain, even at peak Immortal-rank, your power will come very close to the strength you wielded as a low Radiant-rank during our fight in your mind. And once you reach Radiant-rank with nine-circle spellcasting… well, you'll surpass even that."
Her eyes widened slightly, and for a moment, I could see the gears turning in her head. Rin wasn't the type to rest on laurels—or seals, for that matter. The idea of growth, of becoming even stronger, clearly intrigued her.
I couldn't blame her. Her talent really was ridiculous. It was the kind of raw potential that made geniuses look ordinary, the kind that made even the most hardened warriors feel inadequate. But as absurd as Rin's potential was, I wasn't worried.
I wasn't just talented. I was Arthur Nightingale, and if there was anyone capable of standing above even someone like her, it was me. Besides, Rin was on my side. And that made all the difference.
"I want to learn," Rin said suddenly, her voice quiet but resolute. She stepped closer, her hand brushing against mine with an almost hesitant touch. Her expression softened, her dark eyes meeting mine. "So I can protect you this time, my hero."