The sorcerer's taunt, "How very... brave," hung in the cold, dead air. Kaito didn't bother with a reply. In one fluid, economical motion, he shoved Aiko behind him, placing his body between her and the masked figure, his hand already gripping the hilt of the spiritual blade at his side.
The robed man chuckled, a dry, rustling sound that grated on the nerves. "The mighty Ishikawa heir, reduced to a bodyguard for a stolen light." The white porcelain mask tilted, its empty eyes seeming to focus directly on Aiko, through Kaito. "Did you even know what you had, little miracle? Or did you just stumble upon a power you couldn't comprehend? You have been a beacon in the darkness since the day you healed the Onryō. A beacon that screamed 'Here I am!'"
Aiko's blood ran cold. They hadn't just been discovered. They had been lured.
"The Kageyama were clumsy fools," the sorcerer continued, his voice a droning monotone, as if lecturing students. "They tried to buy a cure for a disease they didn't understand. But you... you are the cure itself. And I am here to collect you."
He didn't move. He simply raised one robed hand.
The black, pulsing heart-stone on the pedestal behind him flared with a sick, violet light. A tendril of pure, corrosive blight—a solid-looking ribbon of black energy—lashed out from the stone. It didn't aim for Kaito. It whipped past him, fast as a striking snake, aiming directly for Aiko's chest.
"Aiko, shield!" Kaito roared.
There was no time to think. Aiko threw her hands up, and her training, her fear, and her pure, divine instinct converged. She didn't create a bubble; she projected a flat, golden wall of the Kirin's light.
The black tendril slammed into the golden shield with the sound of a thousand hissing snakes. It was a physical impact. The light held, but the force of it threw Aiko back a step, her boots skidding on the metal grate. The blight hissed and recoiled, the pure, holy energy of the Kirin an agonizing poison to it.
But the sorcerer just tilted his head, intrigued. "So, it is true. You are not just a beacon. You are a weapon."
He raised his other hand. Two more tendrils, thicker this time, erupted from the stone. They lunged at Aiko's shield.
"Kaito, I can't hold it for long!" Aiko cried out, gritting her teeth. The force of the multiple impacts was rattling her bones. Her light flickered, the strain immense. She was a dam holding back a tsunami of pure malice.
The sorcerer was focused entirely on her, on her light, on breaking her concentration. It was the mistake Kaito had been waiting for. The man had forgotten about the shadow in the room.
"Stay strong, Aiko," Kaito's voice commanded, calm and deadly.
And then, he moved.
He didn't charge. He didn't run. He unleashed his Kamaitachi blood. To Aiko's eyes, he simply ceased to be in front of her and reappeared directly in front of the sorcerer, a blur of shadow and wind that had crossed the vault in less than a heartbeat.
The sorcerer, his concentration broken, let out a startled gasp. He was fast, dropping Aiko's shield to form a swirling barrier of dark energy around himself. But he was a magic-user. He expected a magical duel.
Kaito was a Yakuza king. He was a brawler.
He didn't try to break the magical shield. He poured his shadow-energy into his arm and, with a gutteral roar, punched through it.
His fist, wreathed in dark, cutting wind, slammed directly into the sorcerer's porcelain mask.
There was a loud CRACK.
But the mask didn't just break. It shattered. And underneath, there was no face. No blood. No bone. There was only a swirling, chaotic vortex of the same black, blighted energy as the heart-stone.
The robed figure wasn't a man. It was a suit of clothes animated by a magical construct. A puppet.
The puppet staggered back, raising its hands, and Aiko felt a sudden, sharp connection.
"Kaito, the heart!" she screamed, her shield dropping as the tendrils retracted. "The puppet! It's not alive! It's connected to the stone! It's just a remote-controlled body! Break the stone!"
Kaito didn't need to be told twice. He saw the puppet gathering its energy for another, more powerful attack. He ignored it. He spun on his heel, grabbed the plasma cutter he'd dropped, and in one fluid, desperate motion, he plunged the superheated, glowing tip of the device directly into the center of the pulsing, black heart-stone.
A soundless, psychic scream of pure, unadulterated agony ripped through the vault.
The heart-stone glowed a blinding, sick violet... and then cracked in two.
The black tendrils vanished. The corrosive wards outside the building died. The heavy, oppressive spiritual pressure that had filled the air evaporated instantly.
The robed puppet stiffened, shuddered violently, and then, as if its strings had been cut, collapsed into a pile of empty clothes and shattered porcelain.
It was over.
They had won.
Kaito stood panting, his hand smoking from the heat of the cutter. He turned to Aiko. She was trembling with exhaustion, her light fading, but she was safe. They were standing in the silent, dark, and now-inert vault, sixteen meters beneath a raging river, but they were alive.
"Aiko," he breathed, taking a step toward her. "Are you—"
Before he could finish, a new sound filled the chamber. Not a magical hiss, but the grating, mechanical groan of metal. Aiko looked up, her blood running cold.
On the ceiling, a hidden, circular hatch, like a bank vault door, was beginning to turn. Kuroda, his puppet destroyed, had just unlocked the vault's true exit. And he was, without a doubt, on his way down.