The moon hung high over Kuoh Academy, casting silver light across the school grounds. The world was quiet, save for the occasional rustling of leaves in the evening breeze.
It was the perfect time to train.
Standing alone in the club's private training field, I took a deep breath, steadying my mind. My spar with Issei earlier had already resulted in Phantom Stride, proving that direct combat accelerated my mutations. But my Sword Birth ability was still stuck at 45%.
If I wanted it to evolve, I needed to push it to its limits.
Taking a step forward, I summoned my swords.
A soft shimmer filled the air, and a dozen blades materialized around me—elegant, silver, and sharp. Each was a part of me, born from my demonic power. Normally, Kiba's Sword Birth allowed him to create demonic swords of various effects—flame, ice, lightning, and more.
But I wanted more than that.
I wanted evolution.
I gripped the hilts of two swords and took a stance. Then, without hesitation, I began.
I moved like a storm. My blades danced through the air, cutting through imaginary enemies. My steps blurred as I activated Phantom Stride, weaving in and out of positions with inhuman speed.
Faster.
Sharper.
Stronger.
Each swing of my sword carved through the empty night, my body moving instinctively, fueled by years of battle experience—both from Kiba's memories and my own instincts as a former human now adapted to this world.
I pushed beyond my limits, pouring more and more demonic power into my swords. My breathing quickened. My heartbeat pounded in my ears.
And then—
Something clicked.
A surge of energy erupted from my body. My blades glowed, their edges shifting, reshaping, transforming. The air around me vibrated with power as my system flashed a notification.
[Mutation Complete.]
• Sword Birth → Abyssal Armory
• New Effect: Forged blades now possess autonomous movement. Can evolve with prolonged use.
I exhaled sharply.
This was beyond what I expected.
I released my grip, letting my swords hover in the air. Unlike before, they didn't vanish when I let go. Instead, they floated, circling around me as if they had a will of their own. I willed them forward, and they moved—fast, precise, like a swarm of deadly steel.
This was no longer just Sword Birth.
This was an army of living blades.
I clenched my fist, suppressing a grin.
If my abilities kept mutating like this, I wouldn't just be an ordinary knight anymore.
I would become unstoppable.
Just as I was about to test my new power further, a sudden presence washed over the area.
A malicious killing intent.
My instincts screamed at me to move. I activated Phantom Stride, dashing several feet back just as a dark spear of energy slammed into the ground where I had been standing. The force of the impact sent dust and debris flying into the air.
I narrowed my eyes, scanning the treeline.
A figure emerged from the shadows—a man clad in a dark priest's robe, his smirk filled with malice.
A stray exorcist.
"Well, well, well," the man sneered. "Didn't expect to find a devil playing with swords out here."
My grip tightened on my blade. This wasn't a simple thug. His aura was strong, his energy sharp like a dagger pressing against my throat. A battle-hardened killer.
My system pinged in the back of my mind.
[Hostile Encounter Detected.]
• Defeating the enemy may trigger further mutations.
A slow smile crept onto my lips.
"Lucky me," I muttered.
This was the perfect opportunity to test my new power.
The exorcist wasted no time. He lunged, his spear of light aimed straight for my heart.
I dodged—my body flickering out of sight with Phantom Stride—and reappeared behind him. My newly evolved blades shot forward on their own, slashing toward him in synchronized strikes.
The exorcist barely managed to twist away, his cloak tearing as my swords cut through fabric and flesh. Blood splattered onto the ground.
"Shit," he hissed, gripping his wounded side. His eyes narrowed. "You're different from the usual devil scum."
I didn't answer. Instead, I lifted my hand, and my floating swords responded—their tips pointing toward him like a predator locking onto prey.
Then, they attacked.
Blades shot forward at blinding speed, forcing the exorcist on the defensive. He swung his spear, deflecting two strikes, but the third slashed across his arm. He staggered back, eyes widening.
He wasn't just fighting me anymore.
He was fighting a storm of blades.
"You bastard!" he snarled, raising his spear. Holy energy crackled around him, and in an instant, he unleashed a massive wave of light energy.
The attack tore through the ground, aiming to incinerate me whole.
I had seconds to react.
Without thinking, I activated Phantom Stride, weaving through the gaps in the attack. My movements blurred, my footwork flawless. Then, with a flick of my wrist, I sent my swords rushing forward—not as separate weapons, but as one singular force.
They merged midair, forming a single, massive greatsword.
[Abyssal Armory Mutation Detected.]
• New Effect Unlocked: Blade Fusion.
I grabbed the hilt of the combined sword and slashed downward with all my strength.
The blade tore through the exorcist's attack like paper.
His eyes widened in horror as my sword carved through his chest.
For a moment, he stood still—shock written all over his face. Then, his body collapsed to the ground, lifeless.
Silence filled the night.
I exhaled, releasing my grip. The fused greatsword broke apart, its pieces returning to my side as individual blades once more.
I had won.
And my power had grown.
The exorcist's body disintegrated into light, his remnants fading away.
My system pinged one last time.
[Combat Victory Achieved.]
• Abilities Mutated: Abyssal Armory (Further Evolved), Phantom Stride (Stability Increased).
• Potential Unlocks Available with Further Training.
I smirked, rolling my shoulders. My body felt lighter, more in sync with my new abilities. The difference between me now and before this fight was like night and day.
But this was just the beginning.
If stray exorcists were wandering into Gremory territory, that meant trouble was brewing.
And trouble meant more chances to evolve.
As I turned to leave, a presence stirred from the darkness of the nearby rooftop.
Scarlet hair gleamed in the moonlight.
Rias.
She had seen everything.
Her blue eyes locked onto mine, a mixture of curiosity and suspicion swirling within them.
For a long moment, neither of us spoke.
Then, finally, she smiled.
"You've been keeping secrets, haven't you, Yuuto?"
I met her gaze, my mind already racing with possible responses.
I'd planned to keep a low profile.
But maybe it was time to change everything.
It wouldn't be good for me to always remain the same.