◆ Role in the Story (Spoilers: Mugen Train Arc and Beyond)

※This section contains significant plot details from the anime and film, including the Mugen Train Arc, Entertainment District Arc, and Swordsmith Village Arc. Proceed only if you are up to date with the series.





Mugen Train Arc – Fighting Alongside the Flame Hashira
Tanjiro’s first mission alongside a Hashira pairs him with Kyojuro Rengoku, the Flame Hashira, to investigate the Mugen Train, where over 40 passengers have mysteriously vanished. Together with Zenitsu and Inosuke, Tanjiro boards the train—unaware that Lower Rank One, Enmu, lies in wait.

Enmu uses his Blood Demon Art to plunge the group into deep sleep. Tanjiro reunites with his deceased family in a dream and is offered a vision of peace and happiness. But through sheer willpower, and with tears in his eyes, he severs the dream, declaring, “I’m the eldest son!”

Awakened, Tanjiro and the others learn that Enmu has fused his body with the entire train. In a race against time, Tanjiro and Inosuke navigate through its fleshy interior to find Enmu’s neck. Tanjiro unleashes Hinokami Kagura: Clear Blue Sky, finally severing Enmu’s core and saving over 200 passengers.

But the victory is short-lived.

Suddenly, Upper Rank Three, Akaza, appears. Severely injured, Tanjiro cannot fight. Rengoku takes on Akaza alone in a fierce duel. Despite his incredible strength and resolve, Rengoku suffers mortal wounds. As dawn approaches, Akaza retreats. Tanjiro throws his Nichirin Blade after him, screaming “Coward!”—but it falls short.

In his final moments, Rengoku tells Tanjiro: “Set your heart ablaze. Live your life with your chest held high.” Tanjiro vows, through tears, to carry on Rengoku’s legacy.

Entertainment District Arc – Deadly Duel Against Upper Rank Six
Four months after Rengoku’s death, Tanjiro, Zenitsu, and Inosuke join Sound Hashira Tengen Uzui on a mission to infiltrate the Yoshiwara Entertainment District. Disguised as courtesans, the trio investigates the disappearance of Tengen’s three wives.

They discover that the district is being haunted by Upper Rank Six, Daki. Enraged by her cruelty, Tanjiro engages her in battle, pushing himself beyond his limits. Using Hinokami Kagura at blistering speeds, he nearly severs her neck but collapses from exhaustion.

Tengen arrives and decapitates Daki—but the true threat emerges: Gyutaro, her older brother and the true Upper Rank Six. The two demons share a single life and must be killed simultaneously.

While Tengen battles Gyutaro, Tanjiro, Zenitsu, and Inosuke focus on Daki. Despite being poisoned and heavily wounded, Tanjiro stands back up. In a combined effort, Zenitsu unleashes his Thunder Breathing, and Inosuke attacks with precision, finally cutting off Daki’s head.

Meanwhile, Tanjiro launches a surprise attack with a headbutt and a poisoned kunai, striking Gyutaro’s neck. With Hinokami Kagura: Sun Halo Dragon Head Dance, Tanjiro severs Gyutaro’s head just as his friends take down Daki—defeating an Upper Rank demon for the first time in over a century.

However, the cost is high. Tengen is gravely wounded and retires as a Hashira. Tanjiro succumbs to the poison, but is saved by Nezuko, who uses her Blood Demon Art to purify the venom.

Swordsmith Village Arc – New Power and Nezuko’s Miracle
After the battle, Tanjiro travels to the Swordsmith Village to have his broken Nichirin Blade repaired. There, he reunites with Mist Hashira Muichiro Tokito and Love Hashira Mitsuri Kanroji. Their brief peace is shattered when Upper Rank Four, Hantengu, and Upper Rank Five, Gyokko, attack the village.

Tanjiro teams up with Genya Shinazugawa to fight Hantengu, whose four emotion-based clones prove a formidable challenge. Recalling Zenitsu’s movements, Tanjiro executes a lightning-fast strike—hinting at a new style that blends Thunder Breathing with Hinokami Kagura.

After Muichiro defeats Gyokko, he tosses Tanjiro a newly forged blade. With it, Tanjiro lands a decisive blow on Hantengu’s true form, finally slaying him.

But dawn approaches—and Nezuko, as a demon, is vulnerable to sunlight. She sacrifices herself, kicking Tanjiro away to save others. In anguish, Tanjiro finishes the mission and turns to witness an impossible sight:

Nezuko stands, unburned in the morning sun.

She has conquered the sun—a feat no demon has ever achieved. Overcome with emotion, Tanjiro cries out her name, and Nezuko smiles and replies, “Tanjiro,” speaking as a human for the first time since her transformation. The two embrace, surrounded by stunned and joyful allies.

Tanjiro not only defeats two Upper Rank demons, but also rescues his sister from the curse of demonhood. Nezuko’s miracle sends shockwaves through Muzan Kibutsuji’s ranks, signaling the beginning of the story’s final chapter.

Source : DemonSlayer Official