He stood above the fallen boy, chest heaving, body steaming. Yet the yin he had swallowed still swirled inside him, heavy and dark. He could feel it resting there—a second heart, pulsing within his core, waiting for his call.
Ranmaru flexed his fingers, now human once more, though faint traces of black lingered beneath the skin. His gaze dropped—lowering to the unconscious yokai-child, tangled in its own sticky threads, lips faintly moving in dream-mutterings. An unspoken thought shadowed his face.
The wind shifted.
From the treeline, the smell of ash and brimstone drifted in, sour and bitter, heavier with every breath. The shadows bent, and the night itself seemed to recoil.
A voice, ragged and deep as if torn from the pit of Jigoku, thundered through the clearing:
"Hayate no Kuro… how dare you play such games with fate."
The earth shook as a figure stepped forth. Towering, horned, its body wrapped in seething darkness that clung like chains. The face was half-burned away, as if it had walked through eternal fire, its eye sockets glowing with hellish red flame.
Ranmaru's blood ran cold. The air felt wrong—the weight of it pressing into his bones. This was no mere beast. This was a yokai born of calamity.
The fiend's lipless mouth curled into a grin.
"Did you think you could vanish so easily? You tricked the Wanyūdō with a false corpse. You mocked the underworld with your deceit." Its flesh knit together, reddening as charred skin bubbled back to life.
Its clawed hand pointed at the boy at Ranmaru's feet, then curled accusingly toward him.
"And now I see you standing here, meddling with blood that is not yours to claim. Even after your father's death, the Hayate still practice these vile rituals." The yokai growled, raising its kanabō—
The impact struck Ranmaru's arm like a hammer.
His jaw clenched as his body was flung back, crashing through bark and splintering trees. His ears buzzed, bones fractured, breath torn from his chest.
The yokai's laughter rumbled like an earthquake, shaking branches from the canopy.
"But I do have to thank you," it spoke, tusks forcing their way from its gums. Its eyes glowed redder, a black beard sprouting thick across its jaw. "Since it has been a long while since we oni were legally allowed to leave hell."
The oni laughed, stepping toward the rubble where Ranmaru lay buried. Its massive feet sank deep into the soil, its body swelling, bulking until it towered like a mountain.
"Hmm!?" Its brows twisted. The oni's nose twitched, scenting the air. "Still alive."
It looked toward the broken heap of trunks and branches and raised its weapon high before striking down with all its weight.
Boom!!
A violent explosion of dust and rock shook the forest, stones and shattered wood scattering like shrapnel. Beneath the strike, bones crunched. The oni smiled wide, assuming its prey broken—nothing more than blood and ruin.
But then—
The rubble shifted.
A clawed hand shot free from beneath the wreckage, tearing earth apart as Ranmaru rose. His body steamed, flesh split as a crimson hue spread across his skin. Horns burst from his skull, curving upward like a demon's crown. His fingers lengthened, talons gleaming under the fractured moonlight.
The oni's eyes widened just before Ranmaru's fist connected.
The blow landed with such force the oni was launched backward, its titanic body smashing through trees, tearing the forest apart as it skidded across the dirt for dozens of paces before finally grinding to a halt.
Ranmaru stepped free of the wreckage, horns glinting, claws dripping with his own steaming blood. His breath came heavy, ragged, his gaze locked on the oni with predatory fury.
"That didn't even sting," Ranmaru murmured, clutching his chest. His lips twisted into a grin. "If this is all hell has, no wonder your kind lets evil spirits slip through so easily."
The oni's eyes narrowed, tusks grinding together. "What a vile technique you possess," it growled, voice thick with disgust. The chains of shadow about its frame writhed as it studied him. "You dare twist your flesh into our image? A mockery of oni blood…"
Ranmaru only laughed. His body pulsed with heat, bones popping, muscles swelling. Crimson flushed across his skin as if blood itself burned beneath it. Horns tore free from his skull, curling wickedly as black lines of corruption etched across his body like tattoos alive with power. His fingers cracked and lengthened, claws glinting wet with ichor.
The oni raised its kanabō with a roar, but Ranmaru was already moving.
Steel sang.
From his side, the sword flashed into his grip, the blade veined with his qi, warping into a glorious field of lightning. One swing ripped the air apart. The slash struck the oni's weapon head-on.
The forest exploded.
Trees shattered in waves, collapsing like stalks of bamboo beneath a storm. The mountain itself groaned, dust and boulders tumbling from its slopes. The oni staggered back, snarling, before answering with a strike that split the earth in a line stretching far into the night.
Ranmaru spun aside, talons biting deep into the soil for purchase. His sword blurred in his grip—one hand of flesh, one clawed, both feeding qi into the steel. With each slash he carved arcs of unseen bolts, colliding against the oni's strikes with detonations that stripped the forest bare.
"You call me vile," Ranmaru spat, blood steaming off his skin. His horns glinted in the firelight of their battle. "But tell me—what is more monstrous? To be born of hell, or to steal hell's strength and still call myself man?"
The oni roared, swinging its kanabō in a wide arc. The strike shattered the ground into a crater, yet Ranmaru leapt skyward, his horns gleaming like a crescent moon. With both claws wrapped around the hilt of his blade, he descended, qi roaring through him like a furnace.
The impact split the air.
The oni stumbled, roaring in pain as the sword bit deep into its shoulder, carving flesh and shadow alike. But before Ranmaru could wrench it free, the beast's other fist crashed into him. The blow shook the mountain slope, hurling him through stone and earth until he slammed into a cliffside, his body half-buried in rubble.
For a moment, silence. Then—
A laugh, dark and steady, rumbled from the dust.
Ranmaru rose. His skin was torn and bleeding, yet his frame only swelled further—horns lengthening, jaw sharpening, his teeth baring into fangs. His eyes burned red like the oni's own. The sword in his hands trembled, then flared with crimson qi, the steel screaming in rejection.
Step by step, he walked free of the rubble, the ground cracking beneath his weight.
The oni's grin faltered.
This was no human. No hunter.
This was an oni born in battle.
Ranmaru shook free of the rubble, his transformation complete. The Yin-Devouring Yang Beast Technique was an instant power-boost—burning qi and refining it into raw strength.
But this was only its secondary purpose.
At its core, it was a dual-cultivation method, absorbing yin and converting it into qi—later twisted into a combat technique when practitioners discovered they could reverse the process and burn the converted energy.
Thus was born the Yang Beast Series.
Ranmaru crouched. His leg bulged with coiled power as he prepared to unleash his trump card.
"Twin Elephant Veins," he growled.
His body ignited into a torrent of heat, muscles bulging into grotesque masses that stretched skin and bone. Veins glowed like molten lava. Let's end this, he vowed rather than thought, as his blade ignited with lightning.
The sound of an elephant's trumpet roared through the air as his foot struck the ground, launching him forward. Grass caught fire in his wake, the air whistling like a blade.
The oni raised its weapon to block.
"Twin Tusks!" Ranmaru roared, snapping both legs forward with destructive force.
The clash rang with the sound of metal breaking and sizzling, followed by a sharp, pained hiss.
His feet speared through the yokai's chest. Twisting, he rolled into a ball and kicked off. His katana followed the motion, its edge carving through the oni's neck artery and down across its abdomen.