Ignore the Zenkai one
Shinsu walked toward Kai, each step echoing like death itself was calling.
"Meeting you, Kai, was supposed to be a blessing," he said, voice low and cold.
"I found you as a baby. Controlled you as a toddler. But when you grew, everything changed. Your mana devours mine—like wildfire consuming dry leaves—and I became the prisoner, not the host. Imagine it: a two-hundred-year-old demon, caged by a child. Pathetic."
The demon cackled lightly, raising his hand as a pale light pulsed in his palm. Shinsu's eyes narrowed, glowing bright purple.
"Can't be too mad though. Pain makes for good revenge."
The glowing hand descended toward Kai's stomach—until a deafening bang split the air.
Shinsu froze. His head snapped toward the ruins of the dojo. Smoke curled upward like ghostly fingers clawing at the sky.
"Was that… a voice?" he thought, scanning the wreckage. Silence.
Then another bang.
Shinsu's eyes widened as a vortex of red mana erupted from the rubble, swirling with heat and fury.
"How beautiful. To think someone as weak as him could achieve this. A zenkai of such prowess… from a half-breed. Might even surpass a full-grown one."
The demon's praise twisted into a grin. "How fortunate. Killing you would've ended the fun with Raikou."
He stepped closer to Kai, ignoring the flames behind him. His gaze fell on the fallen prodigy.
"Even weak, you're still useful to me and my fu—"
A sudden blow to his torso silenced him.
"Don't even try," Raikou growled, his hand bursting through flesh. Purple liquid splattered across the ground, dripping from his blood-soaked hand.
The boy stood before the demon, panting heavily, eyes burning a savage crimson. He laughed, tilting his head toward the corpse.
"Tell me, demon. How's it feel to die from someone as weak as m—"
Raikou gasped as Shinsu rose again. The demon cracked his neck, glaring with malice.
"How annoying," Shinsu muttered, pressing a hand to his missing torso. "Heal." Flesh knitted instantly.
"Damn you," Raikou spat, fists clenched.
Their glares clashed like predator against predator. But which one was prey?
Shinsu lifted his hand, taunting. "Come on then. Hit me. See how much damage you'll do now."
"Bastard," Raikou snarled, launching forward. Yet as he closed in, Shinsu remained motionless.
Raikou slowed. "What's he planning?" He stopped, closing his eyes. A red aura radiated from him like molten steel.
Shinsu chuckled, purple mist swirling around his hand. "Do you really think you can gain enough power that quickly? You're wide open. I could kill you now."
The mist condensed, raging like a tornado in his palm.
"How odd," Shinsu mused. "The boy is calm… as if guided by something. But who?"
His thought ended as Raikou vanished.
"Thanks for waiting," Raikou said from behind, watching the demon's severed hand fall to the floor.
Shinsu gasped. "Remarkable. Truly remarkable. To cut me is a goal in itse—"
"Shut up," Raikou snapped, slamming his face into the ground.
"Hearing your voice". Raikou stands up. "Is as worst as the flames of hell".
The demon spits blood. "Too bad. Cuz my voice isn't gonna die out just yet".