"So you're telling us you're fifteen now?" Himori and Yuri asked in unison, their voices echoing through the vast, silent aisles of the library. They stared at me as if I were a puzzle missing half its pieces.
"Yeah… I mean, couldn't you tell?" I replied, awkwardly scratching the back of my head, feeling the heat creep up my neck.
"No!" Himori shouted, her sharp eyes scanning me with blatant disbelief. "You're way too tall, and you carry yourself with way too much maturity for a fifteen-year-old!"
"Well, after the ritual that shattered my seal, I went through a bit of a growth spurt," I said, shifting my weight. "And battle strategy… that was kind of hammered into my head by my big sister, Kiyomi."
"Kiyomi was your big sister?!" Himori's weary eyes snapped wide with shock. "She's the one who taught us the fundamentals of the blade and…"
"She's the best sword wielder alive, I know," I said, cutting her off. My voice dropped an octave, the phantom weight of Kiyomi's hand on my shoulder returning for a fleeting second. "She's not my biological sister, though. She just… took care of me."
Himori blinked, the analytical light in her eyes softening into something resembling empathy.
"Oh… I didn't actually know that. I never knew her on a personal level. She was always so cold, so distant while she was teaching us."
"Yeah, I'm gonna have to disagree with you there," I said, a light, genuine grin breaking through my somber mood. "Kiyomi is a huge softie. You should've seen her hugging me every morning and every evening, even when I came home from school. She was absolutely crazy." I laughed softly, the sound hollow in the massive room. "Though, grinding me to the bone during training was her only real hobby."
"That is... unexpected information," Himori murmured, her gaze lingering on my face as if reading the history written there. "You miss her deeply, don't you?"
"Yeah… a lot, actually," I replied quietly, staring at the flickering candle. "I just miss her bright smile and….."
"Master…!"
The heavy atmosphere was punctured by a sudden, sleepy stir from my back.
"Finally," I said, my expression softening.
"Hello there, sleepyhead."
"Master… Master is carrying Esta?" she asked, her yellow eyes blinking up at me, hazy with the remnants of dreams.
"Yeah. You were out like a light, so I figured I'd carry you for a while."
She let out a soft contented hum and rubbed her face against my bare shoulder. Her movements were slow, feline, and deeply affectionate. "Thank you, Master."
"Don't worry about it," I replied gently, though the weight was starting to make my muscles ache. "Now… do you think you can get down?"
"Yes master"
She hopped off my back with surprising grace and immediately began skipping ahead, suddenly overflowing with restless energy. I stayed behind for a moment, lost in the shadows of my own thoughts. I watched the three of them the two high-human sisters and the living blade walking together, arguing, laughing, and moving forward into the unknown without a shred of hesitation.
Do they really believe I can get them out of this alive? Or is it just blind trust?
I still have to face two more of the strongest beings in this runes before I even reach the Witch herself. I can only pray she isn't as monstrously powerful as these High Humans, or I'm going to be a corpse before this mission even nears its end. I have no desire to be a pawn in demon politics. Even if I tried to reason with the Dragon Lord, he wouldn't listen to a 'mongrel' like me. He'd just rip my guts out.
For now, my only path is through. I need to stay with Yuri and learn. I need to master this surging power before it masters me. I can't afford to lose control again. When I removed my ring during the last fight, I didn't succumb to the darkness entirely. I managed to pull myself back. Was it the heat of battle? Or was it...
My eyes drifted to Yuri's cold, confident figure leading the way. As if she felt the weight of my stare, she stopped and looked back.
Our eyes met.
My face flushed a hot, violent red instantly.
"What are you staring at, demon?" she barked, her voice like cracking ice.
"I'm looking at you," I muttered under my breath, then realized I'd said it out loud. "I ..I mean! I'm looking at nothing! Just space!" I stammered, frantically waving my hands.
"Good," she snapped, turning her back to me. "Don't look at me like I'm some kind of specimen."
Sheesh… she's a glacier when she wants to be. I wonder what actually goes on behind that frozen mask?
"Justin," Himori said, her tone shifting back to her scholarly roots as she adjusted her glasses. "Mind if I study your blade? I want to verify a theory."
"Yeah, sure wait," I paused, blinking. "How do you know my name?"
"Oh, Yuri mentioned it while you were trailing behind us earlier.and you told me remember "
"I see.the battle with Yuri must've scrambled my brain" I scratched my head with awkward smile, looking toward Esta. "One problem, though. I actually don't know how to turn her back into a sword."
"Oh? Perhaps the artifact itself knows the command," Himori suggested.
"Esta," I called out, my voice echoing. "I need you."
"Okay, Master!" she chirped, her yellow eyes glowing as she skipped back toward me.
I couldn't help but feel the disconnect again. She has the mind of an eight-year-old, yet her physical form is that of a woman. It's unsettling.
"Esta," I asked gently, kneeling down . "Why do you act like such a child? I don't mean to be mean, I'm just curious."
"Hmmm?" She tilted her head, studying my features with a sudden, unnerving intensity. "Yes, Master." She beamed a smile that felt far too bright for this dark place. "Esta acts like this because no Demon Lord in history has ever had enough mana to summon Esta in her adult form. This is the closest Esta has ever been to my final state."
Her smile widened, revealing teeth that looked just a bit too sharp. "Master is the only one strong enough to bring me out like this. Master fed me so, so much power." She squeezed my hand, and for a second, I felt the sheer magnitude of the bond between us.
That explained the sudden drain I felt earlier. My mana wasn't just wasted; it was an investment. A measurement. The more mana you pour into the steel, the more human the spirit becomes. But if this is just her personality... what is her true function?
"Esta," I asked, looking her dead in the eye, "what is your true power?"
"Esta… doesn't know," she said softly, her gaze dropping to her bare feet. "Esta doesn't know her full power yet."
"Oh… well, that's a bit of a letdown," I sighed, standing back up.
"Let me examine her," Himori said, a small, knowing grin appearing. "I might be able to decipher the enchantments. It is clearly a high-level magical artifact."
"Back to the first problem," I reminded her. "The sword form?"
"Oh, that's easy!" Esta giggled. "Just hold Esta's hand and say 'Transform.'"
I took her hand. It felt warm, vibrating with a strange energy. She smiled at me one last time.
"Transform."
Her body was instantly swallowed by a violent, pulsing purple light. The glow flared once, illuminating the entire library, then collapsed inward. In my hands sat the heavy weight of the blade. It was larger than before, but then, the metal began to groan and shift.
The sword reshaped itself with fluid, terrifying precision. The broad blade narrowed, shortening and refining its edge until it became a sleek, perfectly balanced katana. A faint, rhythmic purple glow emanated from the gem at the hilt, reflecting like a heartbeat along the razor-sharp steel.
"…The full transformation," I whispered, impressed despite myself.
I handed the hilt to Himori. Her eyes lit up like a child in a candy store as she began examining every etched rune and shimmering curve, completely lost in her research.
I walked quietly beside them, the only sound the soft thud of our boots. One sister was obsessed with my weapon; the other was a silent wall of cold confidence. The power gap between Yuri and me was like looking up at a mountain. I could feel the sheer pressure of her mana. Yet, she had no finesse, no strategy just a berserker's thirst for blood.
Is it a curse? Or is she just built for slaughter? I'll probably never get an answer.
I let out a long, weary sigh.
"Oh!" Himori suddenly shrieked, her voice high with discovery. "I've found it! I know what she is!"