Demon Slayer’s Muzan Might Be the Most Incompetent Villain in Shonen

2 weeks ago 19

Published May 10, 2026, 8:30 AM EDT

Casandra Ronning is a staff writer for Screen Rant's anime section. Since mid-2024, she has dedicated herself to expanding her knowledge and experience in the entertainment industry. She is most proud of conducting an exclusive interview with popular voice actor Stephanie Nadolny.

For over a thousand years, Muzan Kibutsuji stood as the most powerful and most feared demon in Demon Slayer. As the progenitor of all demons, he stands at the center of every conflict in the series, becoming a being known for his cruelty and obsession with becoming a perfect, immortal being. Operating from behind the scenes, Muzan felt nearly untouchable, and his control seemed near absolute.

However, in reality, it’s far from the truth. While Muzan has kept himself alive for centuries, his paranoia, ruthlessness, and desire for control ultimately hold him back. When looking at the patterns and decisions he has made, it’s hard not to see the many faults that shape his character and prevent him from reaching his goal. Muzan’s greatest obstacle in Demon Slayer is none other than himself, and his missteps might just make him shōnen’s most incompetent villain.

Muzan Spent Centuries Missing What Was Within Reach

Muzan as seen in Demon Slayer confronting Ubuyashiki

Muzan’s existence is centered around achieving a single goal. He wants to overcome his one fatal limitation and achieve true immortality by either finding the Blue Spider Lily, the flower tied to his original transformation and the key to stabilizing his condition, or creating a demon capable of surviving sunlight like Nezuko Kamado.

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While Muzan is already immensely powerful, the sun has always been a major threat to his existence as a demon, driving him to go to extreme lengths to search for the answer to his weakness. In response to this limitation, he builds an army and experiments constantly, all in pursuit of a perfect, eternal form that’s not bound to the shadows.

Yet, his search was fundamentally flawed from the beginning. Given that the Blue Spider Lily only blooms during the day for a short time each year, it's practically impossible for demons to find it when they’re restricted to searching in the night. So even with an extensive network of demons under his control, Muzan is chasing something that his own kind is essentially incapable of finding, turning every search into a blind operation.

Kimetsu no Yaiba · Final Selection How Well Do You Know Demon Slayer? “Set your heart ablaze.”

🗡TanjiroThe kind-hearted blade

🎋NezukoThe sleeping demon

🔥HashiraNine pillars

👹MuzanProgenitor of demons

🌊BreathingTotal concentration

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The series follows a young charcoal seller whose family is slaughtered by a demon. Only his sister Nezuko survives — turned into a demon herself. What is the protagonist’s full family name?

ATanjiro Agatsuma BTanjiro Kamado CTanjiro Tomioka DTanjiro Hashibira

✓ Correct! Tanjiro Kamado is the eldest son of the Kamado family of charcoal-makers. The Kamado name, written with characters meaning “furnace,” is a subtle nod to the family’s ancient connection to fire and Sun Breathing — the original breathing style all others descend from.

✗ Demon deception! The answer is Kamado. Agatsuma is Zenitsu’s surname, Tomioka is the Water Hashira Giyu’s, and Hashibira belongs to the boar-headed Inosuke. Tanjiro Kamado’s family lived high in the mountains as charcoal-burners — a lineage that secretly carried the art of Sun Breathing.

Demon Slayer: Kimetsu no Yaiba began as a serialized manga in Weekly Shonen Jump in 2016 before becoming a global anime phenomenon. Which mangaka created it?

AHajime Isayama BKoyoharu Gotouge CEiichiro Oda DMasashi Kishimoto

✓ Correct! Koyoharu Gotouge is famously private — the pen name gives no indication of gender, and the author has consistently declined interviews and public appearances. The manga ran for 205 chapters from 2016 to 2020 and sold over 150 million copies, making it one of the best-selling manga of all time.

✗ Demon deception! The answer is Koyoharu Gotouge. Hajime Isayama created Attack on Titan, Eiichiro Oda writes One Piece, and Masashi Kishimoto created Naruto. Gotouge wrapped Demon Slayer’s main story in 2020 after just four years — a surprisingly short run for a series of that scale.

Before the Final Selection, Tanjiro trains for two years on Mount Sagiri under former Hashira Sakonji Urokodaki. Which breathing style does Urokodaki teach him?

AWater Breathing BThunder Breathing CFlame Breathing DStone Breathing

✓ Correct! Water Breathing has ten forms plus the Eleventh Form (Dead Calm), the last of which was created by Urokodaki’s finest student, Giyu Tomioka. Tanjiro later combines Water Breathing with his family’s ancestral Hinokami Kagura (Sun Breathing), which proves far more powerful against high-ranking demons.

✗ Demon deception! The answer is Water Breathing. Thunder Breathing is Zenitsu’s style, Flame Breathing is the Rengoku family’s specialty, and Stone Breathing belongs to Gyomei Himejima. Urokodaki was the Water Hashira decades before Giyu, and his pupil Tanjiro eventually surpasses him by unlocking Sun Breathing.

Nezuko Kamado is the only known demon allowed to travel with the Demon Slayer Corps — she wears a bamboo muzzle and is carried in a sealed wooden box by day. What makes her so uniquely valuable to her brother’s cause?

AShe can shift her size at will BShe’s immune to sunlight from the start CShe sleeps for nourishment instead of eating humans DShe can speak with other demons telepathically

✓ Correct! Nezuko restores her body and power by sleeping, bypassing the need to consume humans that defines every other demon. Her unbroken love for her brother — and her implanted suggestion from Urokodaki that all humans are her family — anchors her humanity. She does eventually gain sunlight immunity, but that’s a much later plot twist.

✗ Demon deception! The answer is that she sleeps instead of feeding on humans. Nezuko can change her size (true but minor) and eventually gains immunity to sunlight (near the end of the series), but her defining trait is that she refuses to eat humans — sustaining herself through long periods of sleep instead.

The series’ ultimate antagonist is the original demon — a creature who has walked the earth for over a thousand years, creating every other demon from his own blood. What is his name?

AAkaza BDouma CKokushibo DMuzan Kibutsuji

✓ Correct! Muzan Kibutsuji is the Demon King — created accidentally by a Heian-era doctor whose medicine overcame his terminal illness but turned him into an immortal monster. His lifelong obsession is curing his sunlight weakness. Akaza, Douma, and Kokushibo are all Upper Moon demons under his command — terrifying but all creations of Muzan himself.

✗ Demon deception! The answer is Muzan Kibutsuji. Akaza (Upper Moon 3), Douma (Upper Moon 2), and Kokushibo (Upper Moon 1) are all fearsome Twelve Kizuki, but they’re Muzan’s creations — not the original demon. Muzan is the source of every demon in the story, and destroying him ends the demon curse forever.

The Mugen Train arc features Tanjiro being mentored by the cheerfully boisterous Flame Hashira — a man whose final words (“set your heart ablaze”) became a fandom rallying cry. What is his name?

AKyojuro Rengoku BGiyu Tomioka CTengen Uzui DGyomei Himejima

✓ Correct! Kyojuro Rengoku — the Flame Hashira with the iconic yellow-and-red flame-haori and the signature “UMAI!” catchphrase — battles Upper Moon 3 Akaza in one of the series’ most devastating fights. His death and final speech to Tanjiro became one of the most emotionally impactful moments in modern anime.

✗ Demon deception! The answer is Kyojuro Rengoku. Giyu Tomioka is the Water Hashira (the stoic one who saves Tanjiro and Nezuko in episode 1), Tengen Uzui is the flamboyant Sound Hashira from the Entertainment District arc, and Gyomei Himejima is the gentle-giant Stone Hashira — the Corps’ strongest.

Demon Slayers wield Nichirin Blades — color-changing katanas forged from sun-infused ore. When a slayer first draws theirs, the blade takes on a color reflecting their breathing style. What color does Tanjiro’s blade turn?

ABlue BGreen CRed DBlack

✓ Correct! Tanjiro’s blade turns black — an extremely rare color associated in-universe with bad omens and the superstition that black-blade wielders don’t live long. The real reason, revealed later, is that black blades resonate with Sun Breathing, the original breathing style from which all others descend.

✗ Demon deception! The answer is black. Water Breathing typically produces blue (like Giyu’s), Mist Breathing produces a pale greenish-white, and Flame Breathing a vivid red-orange. Tanjiro’s pitch-black blade is considered unlucky — but it’s actually the mark of a Sun Breathing user, the rarest and most powerful style of all.

The 2020 anime film Demon Slayer: Mugen Train became a worldwide box-office phenomenon despite releasing in the middle of the pandemic. What record did it famously break in Japan?

AIt won the Oscar for Best Animated Feature BIt became the highest-grossing Japanese film ever, surpassing Spirited Away CIt was the first anime to win the Cannes Palme d’Or DIt was the first anime film to surpass $1 billion globally

✓ Correct! Mugen Train dethroned Hayao Miyazaki’s Spirited Away, which had held the Japanese box-office record for 19 years. Ufotable’s breathtaking animation of the Tanjiro-versus-Akaza battle, paired with Rengoku’s emotional farewell, turned a theatrical arc of the anime into the highest-grossing film in Japanese history.

✗ Demon deception! The answer is that it surpassed Spirited Away as Japan’s highest-grossing film ever. Mugen Train didn’t win an Oscar (though it was eligible) and hasn’t crossed $1 billion globally. But in Japan, it dethroned Miyazaki’s 2001 classic — a record many thought would stand forever.

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Beyond that, the most ironic part of his centuries-long search is the fact that the Blue Spider Lily was right under his nose. According to official fan books for Demon Slayer, the flower grows on the grave of his greatest enemy's wife, in the same mountain region where the Kamado family lived, meaning that Muzan was repeatedly in the exact area he needed to be in to find the flower. Yet, due to his limitations as a demon as well as his flaws, he was never able to seize any opportunities to find and harvest it.

Muzan Became His Own Worst Enemy

Muzan’s failure to procure the Blue Spider Lily was due just as much to his own personal flaws as external circumstances, if not even more so. Muzan is known for his arrogance, obsessive need for control, and paranoia, all of which are traits that turn whatever advantages he could have had into liabilities. Rather than creating a system that can compensate for demons’ limitations, he instead creates one that prioritizes obedience and fear over effectiveness and information.

This is a pattern he’s fallen into since his origin, beginning with the moment he kills the doctor responsible for his treatment before it's fully completed. By killing him out of impatience and frustration, Muzan eliminates the one person who fully understood the Blue Spider Lily’s role in his condition. What could have led to a breakthrough instead led to a dead end that Muzan later came to regret for entirely selfish reasons.

In the end, Muzan’s downfall stemmed from his shortsightedness and hubris.

However, that was only the first of many missteps he took in his long life. Since he views humans as inferior beings, he never seriously considered relying on them to search for the flower on his behalf in exchange for a reward or even false promises. By solely entrusting demons, who are incapable of searching during the day, he repeats a cycle of ineffectiveness.

Paired with other missteps, such as avoiding direct confrontation with the Demon Slayer Corps for centuries, killing his own Lower Ranks following Rui’s death, essentially doing the Demon Slayer’s work for them, or underestimating Kagaya Ubuyashiki long enough to be caught in a fatal trap, Muzan’s centuries-long life has been one mistake after another.

In the end, Muzan’s downfall stemmed from his shortsightedness and hubris. Had he swallowed his pride and overcome his paranoia, he could have been a far more effective and threatening villain in Demon Slayer. Instead, due to his countless shortcomings, he’s arguably one of shōnen’s most incompetent.