The cave was silent, with only the faint tremor of ice crystals and Cheng Mo's heavy, suppressed breathing.
No one knew of this silent yet brutal, precise war waged on the soul level.
Hei Yu, sensing his master's extreme focus, locked his crow eyes on the cave entrance, vigilant for any unexpected occurrences.
Time seemed to stretch.
Cheng Mo's entire mind was immersed in it, and everything external was blocked out.
Sweat gathered into beads on his forehead, rolling down his stern profile and splattering on the cold rock, yet he was completely oblivious.
His gaze was intensely focused, and his fingers trembled slightly and unconsciously on his knee, mimicking the precise, millimeter-perfect stripping action at the soul level.
His past experience in exercising extreme control over Lightning Release Chakra was now perfectly applied to the delicate manipulation of soul energy.
Every iota of mental power output had to be precise.
When more than half of Muzan's fragment had been stripped away, an anomaly suddenly occurred!
The dark red mass of defiled energy seemed to realize its end was near and violently contracted.
It was no longer struggling, but rather exuded an extremely malicious, self-destructive, insane will!
It attempted to condense its last bit of power into a single point for a final counterattack.
It even wanted to self-detonate, dragging Kamiya Kawayuki's remaining soul essence down with it to perish together!
Cheng Mo's gaze suddenly turned cold, and he inwardly shouted, "Dream on!"
The contingency he had long prepared was instantly activated!
Several energy threads, thinner than hair but imbued with stronger mental power and purifying properties, instantly intertwined from all directions.
Like a precisely woven net suddenly tightening, they firmly enveloped and compressed the fragment attempting to self-detonate.
It was tightly confined within an extremely small range!
At the same time, he separated another portion of energy threads and, with the fastest speed, precisely severed the last few connection points between the fragment and Kawayuki's soul essence!
"Sister!"
Ying's thought cried out, filled with unprecedented tension and anticipation.
She, too, was doing her best to stabilize Kawayuki's consciousness, which was on the verge of collapse under the impact of intense pain.
Swoosh—
The last stubborn connection was completely severed.
The dark red fragment, compressed into a single point and thrashing wildly, was like duckweed without roots, flickering madly a few times within the intricate network of soul energy.
Finally, it rapidly dimmed, annihilated, turning into the finest energy dust, completely dissipating into nothingness, no longer detectable in the slightest.
Within the ice crystal, the unsettling evil aura that had surrounded Kamiya Kawayuki for over a hundred years suddenly vanished.
Her face was still transparently pale, but the century-old pain, malevolence, and struggle in her brows dissipated without a trace, as if dust brushed away by a breeze.
In its place was a deep, utterly exhausted weariness, and a hint of peace.
Even the energy fluctuations emanating from the massive ice crystal became pure and cold, no longer carrying any eerie sensation.
Cheng Mo carefully scanned it several times with the Eye of Truth before finally confirming.
The curse had been completely removed.
Kamiya Kawayuki's soul essence was slightly damaged due to prolonged erosion and the recent stripping, but its foundation was intact, and it should gradually recover after peaceful recuperation.
He pondered for a moment, then activated a trace of gentle Chakra, carefully guiding it into Kawayuki's body, nourishing her long-parched meridians and weakened soul.
As if spring rain had moistened frozen soil, Kawayuki's narrow, frost-laden eyelashes trembled violently a few times, like a butterfly struggling to break free from its cocoon.
She slowly, with extreme difficulty, opened her eyes.
They were a pair of ice-blue eyes, as clear as a high mountain lake, but at this moment filled with bewilderment and deep exhaustion.
She was like an infant waking from a centuries-long slumber, confused and unfocused, surveying this strange world and the sole figure before her—Cheng Mo.
"You... are...?"
Her voice was terribly hoarse and dry, almost just a faint sound of airflow rubbing against her vocal cords.
"Sister... Sister! You're awake, that's wonderful, truly wonderful!"
Ying's thought eagerly merged with her sister's soul.
A century of longing and guardianship, the painful past, and the process of being finally rescued by Cheng Mo, flowed like a tide at the soul level.
Kamiya Kawayuki's pupils contracted slightly, and crystal tears quickly gathered in her ice-blue eyes, rolling down her pale, emaciated cheeks.
The tears instantly solidified into translucent ice beads in the cold air.
She laboriously turned her eyes, looking at Cheng Mo again, her gaze becoming incredibly complex.
It was filled with endless gratitude, deep guilt, and an indescribable excitement of rebirth.
"So... that's how it is..."
Her voice was still weak, but with a hint of understanding and a choke.
"Thank you... my unknown benefactor... Thank you... for giving me... a second life... and for saving... Ying..."
After initially understanding this century-spanning causality, Kamiya Kawayuki struggled, using all her newly recovered meager strength, to prop herself up.
Cheng Mo did not help her, just watched quietly.
She ultimately couldn't sit up completely, leaning against the cold crystal wall, gasping for breath.
But her ice-blue eyes became incredibly serious as she looked at Cheng Mo.
"Benefactor..."
Her voice was weak, but her words were clear.
"My and my sister Ying's remaining lives are your gift... The sins and suffering accumulated over these hundred years... also ended by your hand..."
She took a deep breath of cold air, as if using all her strength, and said each word distinctly: "I, Kamiya Kawayuki, am willing to pledge my body and remaining strength to you, to follow you... until... the moment my soul disperses! And I also implore you, if in the future you can find a way to bring Ying back to the human world, please..."
Her voice carried an uncontrollable tremor, which was her last and deepest wish as an older sister.
Kamiya Kawayuki knew that Cheng Mo wouldn't have gone to such great lengths to save her without expecting something in return.
Besides repaying her life-saving grace, she also hoped that Cheng Mo's miraculous methods and power could one day save her sister.
Cheng Mo looked at the resolve and plea in her eyes, remained silent for a moment, then nodded.
"I accept your allegiance. You will need time to recover your strength; I will provide everything you need. Remember your oath today."
He did not make false modesties or enthusiastic responses, but simply accepted this loyalty born of life-saving grace and a century of salvation.
This calmness, on the contrary, made Kamiya Kawayuki feel even more at ease.
She bowed her head with difficulty, performing a silent gesture of submission.
"Now, it's time to leave."
Cheng Mo stood up.
He pointed his fingers like a blade, Lightning Release Chakra covering his fingertips with extremely precise frequency, lightly tracing the giant ice crystal.
The ice crystal, now without Kamiya Kawayuki's own power to sustain it, was no longer indestructible.
With a series of fine cracking sounds, it shattered and fell like broken glass, revealing the extremely weak girl within.
Cheng Mo carefully carried Kamiya Kawayuki, who was almost unable to stand, on his back.
Her body was cold and very light.
But upon contact, there was no longer any trace of a demon's violent aura, only a deep weakness and pure coldness.
A former Upper Rank Two, once mighty and with blood on her hands, had thus completely changed allegiance.
He adjusted his posture to ensure she wouldn't slip.
Then Cheng Mo moved, transforming into a swift bolt of Lightning Release.
The two left the cave that had imprisoned Kamiya Kawayuki for a century, speeding towards the Asakusa laboratory.