As the first rays of dawn broke on the horizon, a gentle warmth washed over the town, which had borne witness to the climactic clash of the Demon Slayer Corp. Muzan Kibutsuji, the fearsome Demon King, was slowly succumbing to his demise. The thousand-year-old war that had gripped the land had finally reached its long-awaited conclusion. The battlefield bore the scars of an epic struggle—a tapestry of craters from unleashed explosions and fires that now gave way to wisps of smoke, creating an ethereal ambiance. Amidst the devastation, the town's once-proud buildings now stood battered and worn, their history etched in every crack and crevice.
The aftermath of the fierce conflict was evident in the fallen bodies of the demon slayers, strewn across the ground like fallen heroes. The air itself seemed to carry the weight of their sacrifice, infused with the solemn scent of death. Humanity had emerged victorious, but the price paid had been immense.
"We won, we won!"
"UWAHH"
"We beat HIM! We beat Muzan!"
The battlefield echoed with cries of triumph and tears of joy as the surviving demon slayers embraced one another, their voices tinged with disbelief and awe. They had achieved the seemingly impossible, defeating the malevolent force of Muzan Kibutsuji. But amidst their celebration, an air of bitter-sweetness enveloped them - a testament to the price of victory.
As the dust settled, a whirlwind of activity ensued, with the survivors tending to the wounded. Among the fallen, the Hashiras, the pillars of the battle, bore the weight of their sacrifices. They lay strewn across the battlefield. Gyomei Himejima, the unwavering Stone Hashira, sat against the wall, a serene smile gracing his lips. Rejecting aid from the Kakushi, he embraced his destiny, knowing his time had come. The Love Hashira found solace in the arms of the Serpent Hashira, their wounds a testament to their commitment. Together, they faced death with love as their shield, securing humanity's freedom from the demonic menace.
On the ground, the Wind Hashira lay, his wounds tended to by the Kakushi. Breathing still, his soul yearned to reunite with his departed family. In the battle against the upper moon one, he had lost his beloved brother, and grief weighed heavily upon him. As his eyes fluttered open, he muttered but one word— "F*ck" a raw, unrestrained expression of frustration and loss.
As Inosuke's consciousness returned, he swiftly sank his teeth into the surprised Kakushi attempting to aid him, a testament to his unyielding spirit as the King of the mountains. Undeterred by his injuries, his feral tenacity remained unshaken.
Meanwhile, Zenitsu, amidst his own injuries, playfully teased the Kakushi tending to him. With a mischievous glint in his eye, he urged the Kakushi to profess undying love to his imaginary wife, Nezuko. At this moment of vulnerability, Zenitsu's imagination and sense of humor provided a light-hearted respite, even in the face of adversity.
The Water Hashira - Giyu Tomioka forced himself to his feet, his heart pounding in his chest as he frantically searched the battlefield for his young comrade - Kamado Tanjiro. His eyes bore witness to the aftermath of the brutal battle against the demon king which had left the once vibrant town in ruins, mirroring the devastation he felt in his soul.
Scanning the surrounding chaos, and there, in the distance, he saw him—Tanjiro, kneeling on the blood-soaked ground, his blade clutched tightly in his remaining hand. Giyu's heart sank as he rushed toward the boy, but his legs felt like lead, weighed down by the knowledge of what he might find.
As he drew nearer, his worst fears were confirmed. Tanjiro's young face was pale, streaked with sweat and tears, and his once-vibrant eyes were dim. Blood pooled around him, staining the earth, and Giyu's own vision blurred with tears as he saw the extent of Tanjiro's injuries—his arm severed, his body weakened from the relentless battle.
Tears streamed down Giyu's cheeks as the Kakushi approached, their faces somber and sorrowful. They tearfully informed Giyu that Tanjiro was no longer breathing, his pulse gone. The weight of the news was crushing, and Giyu's heart clenched in agony.
Kneeling beside Tanjiro, Giyu reached out with trembling hands and gently grasped the boy's remaining hand. He bowed his head, unable to contain the sorrow and guilt that overwhelmed him. "I'm sorry, Tanjiro," he choked out, his voice thick with emotion. "I failed to protect you... I was supposed to be your pillar of support, but I've let you down."
Giyu's shoulders shook with the weight of his emotions, his thoughts filled with memories of their time together—training, laughing, and fighting side by side. He clearly remembered the first time he had met the pair of brother and sister, how he had stood up against him to protect his sister despite the distinct difference in power between them. He had always admired Tanjiro's unwavering spirit and determination, and now, to see him lying there, life slipping away, was a pain beyond measure.
As he continued to pour out his apologies, Giyu was unaware of the soft footfalls approaching from behind. Nezuko, Tanjiro's beloved sister, had arrived at the scene, her heart breaking at the sight of her brother in such a state. Tears streamed down her cheeks as she ran toward them, her emotions in turmoil.
Giyu's eyes widened in surprise as he felt a presence behind him. He turned, and there was Nezuko, tears glistening in her eyes, a mix of pain and determination on her face. Giyu's heart ached for her, knowing that he had failed to protect her brother, the one she loved more than anyone else in the world.
With a trembling voice, Giyu turned back to Tanjiro, still holding his hand tightly. "Nezuko," he said softly, "I'm so sorry I couldn't protect him. I failed you both." He wished he could undo the pain, and bring back Tanjiro, but he knew he couldn't change the past.
It's at this point where normally according to the canon timeline Tanjiro would be revived as a demon after Muzan infused all his remaining blood into him, proclaiming that Tanjiro would become his legacy, his successor who would inherit all his feelings and undying will to live, becoming a demon lord far more powerful than he had ever been, conquering the sun and vanquishing the demon slayers in his stead.
However, in this alternate timeline, as Muzan extended his hand to infuse Tanjiro with his remaining blood, an unexpected twist of fate shattered the demon king's wicked plans. To his horror, Muzan discovered that Tanjiro had already embraced death's embrace, rendering his legacy scheme futile. The young warrior's body, worn down by the intensity of the night's battle and severe blood loss, could endure no more, even with his unwavering tenacity and will to live.
With his mission of avenging his family complete and believing his sister, Nezuko, would soon return to her human form, Tanjiro smiled brightly, prepared to reunite with his loved ones awaiting him on the other side.
Yet, destiny had one last surprise in store for him. As he traversed the Sanzu River, the river leading to the afterlife, a profound vision emerged from a bubble in the gently flowing waters. It showcased his younger self resting peacefully on a simple tatami mat, on the dawn of the day tragedy struck his family completely shattering his peaceful life and marring him for life. In rapid succession, Tanjiro relived every decision he made since that day, his trials, losses, days of arduous training, and the camaraderie shared with friends. Tears welled in his eyes as he witnessed both the joy and sorrow of his journey.
Then, the vision focused on a heartrending scene—he saw himself kneeling, a broken katana clutched tightly, his sister embracing him with tears streaming down her cheeks. Inosuke and Zenitsu stood by her side, offering support and understanding. And there was Giyu-san, the stoic Pillar, his head bowed in a silent tribute to the fallen hero. Silently, the surviving demon slayers surrounded them, each one carrying the weight of their shared loss—a hero fallen. In that profound moment of reflection, Tanjiro understood the true legacy he had left behind—not the path of darkness Muzan had envisioned but a legacy of camaraderie, love, and hope. His journey had touched the lives of many, inspiring them to stand tall against the darkness.
"We WON! We WON! Even though I died, we won," he told himself, a teary smile adorning his face even as he watched the somber scene before him.
With a serene smile, Tanjiro embraced the revelation. He had achieved what he had set out to do—he had avenged his family, found a cure for his sister, and protected humanity. His heart now rested in peace, knowing that his friends and comrades would live to see old age safe from Muzan. His soul was at ease as he prepared to reunite with his family, who awaited him on the other side.
As Tanjiro wiped away his tears, a foreboding sense gripped him. His keen intuition sensed an impending danger, and to his horror, he witnessed a startling transformation. The tumor on his head vanished, and his once lifeless body opened its eyes, revealing a sinister, demonic gaze. In an instant, his left arm regenerated, swift and unnatural.
Attempting to warn his comrades, Tanjiro struggled to scream, but his voice betrayed him, lost in his constricted throat. Before anyone could react, a Kakushi standing nearby suffered a gruesome fate, his head mercilessly separated from his shoulders in the blink of an eye. The others were paralyzed with shock and confusion as chaos unfolded.
"UGHHH!" Zenitsu's agonized cry pierced the air, his chest pierced by an unknown force. "Zenitsuuuuuuuuuuuuuu!" Tanjiro, his heart aching, joined his friends in calling out Zenitsu's name, a chorus of pain and anguish filling the air.
Dread and desperation consumed Tanjiro as he grappled with the inexplicable reality before him. How could he move and act when he was supposed to be dead? His body seemed to have a will of its own, beyond his control.
The group recoiled, distancing themselves from this enigmatic and dangerous entity—what was once their dear comrade. The sunlight bathed Tanjiro's form, and they gasped in astonishment as his flesh seemed to burn and peel under the intensity of the sun. Yet, just as suddenly, the burnt skin regenerated at an astonishing speed, leaving them bewildered and unsettled.
"T-Tanjiro, what's happening? Why did you... why did you attack Zenitsu?" Inosuke's voice wavered with a mix of confusion and fear, mirroring the emotions coursing through them all.
With an eerie slowness, Tanjiro's figure rose to its feet, its back initially turned to the bewildered group. As it finally faced them, they recoiled in shock at the ghastly sight before them. Tanjiro, or what had once been him, now stood with a sinister countenance. Drooling uncontrollably, he relished the sensation of his newly acquired claws and fangs. The demon slayer mark on his forehead had mutated, extending down past the bridge of his nose, while another identical mark emerged from his neck, nearly meeting the first—a grotesque resemblance to Kokushibo's mark.
"Tanjiro? That troublesome boy is dead," the figure spoke with a deep, bone-chilling voice, eerily reminiscent of Tanjiro's own.
Giyu's voice trembled as he dared to question the incomprehensible truth, "Muzan, how's this possible?"
Unfazed by the question, the Muzan-possessed Tanjiro reveled in his newfound existence, basking in the warmth of the sun he had been denied for a millennium. With an air of sinister triumph, he acknowledged the unforeseen outcome of the blood infusion.
"Even I don't understand what's happening. I was dying, and then this," he mused, his voice tinged with wicked delight. "The blood infusion worked beyond my expectations. I conquered death, and now I conquer the sun. Kagaya Ubayashiki's talk of your demon slayers' feelings, their victories—meaningless in the end. I am free!"
With a savage grin, Muzan, in Tanjiro's body, turned to face them, exuding an aura of malevolence that sent shivers down their spines.
Giyu's urgent voice pierced the stunned silence, rallying the demon slayers from their daze. "Everyone, anyone who can still fight, grab your weapons! The battle is far from over. Muzan lives on, and he has taken possession of Tanjiro's body!" Desperation weighed heavily in his words, the gravity of the situation apparent in every syllable.
Exhausted, injured, and facing dwindling numbers, the demon slayers were caught in a moment of doubt. They had fought relentlessly against the demon king throughout the night, and weariness now gripped their souls. How could they possibly confront this monster who had conquered the very sun, seemingly invincible with no apparent weaknesses? The task felt insurmountable, the odds stacked against them—utterly impossible.
As the possessed Tanjiro stood before them, his demonic gaze piercing their souls, Inosuke's rage flared like a wild beast. "You dare possess our friend's body, you filthy demon!" he roared, brandishing his dual chipped blades, ready to avenge Zenitsu's death.
Giyu, struggling to maintain his composure, raised his Nichirin blade in defiance. His voice steadied, albeit shaken, as he confronted the monstrous aberration before him. "This isn't possible. Tanjiro... what has become of you?" he questioned, his heart heavy with grief and disbelief.
Nezuko, who had been standing silently, her heart in turmoil at the sight of her brother's transformation, finally found her voice. "Tanjiro, please, fight it! Don't let this demon control you!" she pleaded, her eyes brimming with tears.
But Muzan's sinister grin widened, revealing the sharp fangs that had now become a part of Tanjiro's visage. "Ah, my dear sister, you too have joined the pitiful ranks of the powerless. Your words fall on deaf ears. This body now belongs to me, and there's no turning back," he taunted, his tone dripping with malice.
Giyu's grip tightened on his sword, determination flickering in his eyes. "We won't let you escape, Muzan! Even if you're wearing Tanjiro's face, we'll defeat you and bring our friend back!" he vowed, rallying his comrades with his unwavering resolve.
Inosuke's rage reached its zenith, and with a fierce battle cry, he lunged at the possessed Tanjiro, his blades a blur of fury. With a resounding battle cry that echoed through the desolate and destroyed town, the demon slayers surged forward, joining Inosuke's fierce assault. Renewed resolve coursed through their veins, fueled by the legacy of Tanjiro and their fallen comrades. Their unyielding bonds, forged in the crucible of countless battles, shone bright, refusing to be extinguished by the encroaching darkness. Shoulder to shoulder, they faced the daunting figure of Muzan, united in purpose.
Yet, despite their unyielding determination, Muzan's movement was too swift for their exhausted and wounded bodies to react. Undeterred by their fatigue and injuries, they hurled themselves at the malevolent force before them, the fate of humanity resting heavily on their weary shoulders. They charged into the fray, facing the darkness head-on, but it seemed as though the odds were stacked impossibly against them. Muzan's power had reached unimaginable heights, turning the battlefield into a gruesome bloodbath, with dismembered limbs strewn like macabre decorations.
Helpless and shattered, Tanjiro could only watch in horror as everything he cherished was ripped apart before his eyes. He knelt on the bridge overlooking the Sanzu River, his spirit broken, grappling with the devastating loss he had just witnessed.
In an anguished voice, he unleashed a primal yell, rejecting the unbearable reality. "NOOO! This cannot be happening! I refuse to accept this fate. I won't accept it. I cannot die while Muzan still lives!"
Through his pain-filled voice and the fire of vengeance burning within him, something unexpected occurred. In a breathtaking twist of fate, a celestial connection transcended time itself formed with his younger self.
You see, Tanjiro had inherited the legacy and memories of his ancestors, tracing back to the original sun breath user, which empowered him to master the breath of the sun. Now, faced with the death of his comrades and the loss of his only living family, a reversal of time's flow took place. His memories and a fervent desire to prevent this tragedy reached out to his younger self, spanning a vast expanse of time.