10 Smartest Demon Slayer Characters, Ranked

Demon Slayer is one of the most popular modern shōnen anime series to exist and while most of the credits go to Ufotbale’s stellar anime adaptation, the diverse and compelling cast of characters is also a significant factor in its success. On his journey to turn his sister back into a human, Tanjiro comes across a lot of characters that help him grow as a demon slayer. In this limited time, every character manages to leave a lasting impact on the series.

Though the emotional backstories of both demons and humans are a highlight, some Demon Slayer characters stand out due to their exceptional intelligence and strategy. Since demons are superior in strength and abilities, the survival of the demon slayers hinges on their ability to make swift and clever decisions. That said, demons themselves are far from lacking in intelligence. Demon Slayer does an excellent job of balancing both sides, with certain characters shining more brightly when it comes to their wit and ingenuity.

10

Kokushibo

The Strongest Upper Moon Is Filled With Battle Knowledge

The Upper Moon One is one of the oldest beings in Demon Slayer and, with old age, the demon has gathered vast knowledge. This is clearly evident when Kokushibo overpowers not one but multiple Hashiras at once in some of Infinity Castle’s best fight scenes. Kokushibo’s battle expertise stems from a lifetime of relentless training and honing his skills, solidifying him as a formidable warrior.

While his mastery of combat and the development of his unique breathing style are testaments to his intelligence, Kokushibo’s overconfidence becomes his downfall. His decision to abandon humanity in the pursuit of greater power, rather than using his knowledge for good, ironically highlights that one of Kokushibo’s greatest flaws is his lack of common sense.

9

Kiriya Ubuyashiki

In a Limited Time, the New Successor to Ubuyashiki Proved His Inherent Knowledge

The heads of the Ubuyashiki family are placed as the leaders of the Hashiras and guide them against Muzan. After the elder Ubuyashiki’s demise in attempting to kill Muzan, Kiriya Ubuyashiki steps into this role and quickly proves his capability by leading the demon slayers through their final battle against Muzan and his minions, highlighting the inherent brilliance of the Ubuyashiki bloodline.

Kiriya plays a very crucial role in the Infinity Castle and if it weren’t for him, the success of the demon slayers would have been in jeopardy. Despite being new to the job and under pressure, Kiriya seamlessly aids others in their battle. Had he been given a more extended role in the series, his intelligence would have easily outshined many.

8

Giyu Tomioka

Only Hashira to Further Enhance His Breathing Form

Every demon slayer employs a breathing technique, typically consisting of ten forms. However, the current Water Hashira, Giyu Tomioka, stands out as the only known Hashira to expand upon his inherited Water Breathing style by developing an eleventh form. Though the exact process of how Tomioka achieved this remains unexplored, the creation of this technique subtly highlights his intelligence.

Giyu’s intellect is further emphasized through his analytical approach to combat, as he carefully assesses his opponents, never underestimating them. This methodical mindset not only sets him apart from his peers but also arguably positions him as one of the most strategic and intelligent characters in Demon Slayer.

7

Yoriichi Tsugikuni

The Creator of the Breathing Styles is the Pinnacle of Demon Slayers

The twin brother of Upper Moon One, Yoriichi, represents all the best things about Kokushibo and elevates it one step further through his prodigious natural talent. While Kokushibo spent his entire life—and afterlife—honing his skills, he still falls short of his brother’s unmatched prowess. Yoriichi is the creator of the Sun-Breathing style, the original technique from which all other breathing styles are derived.

From his various encounters with Muzan, Yoriichi was able to further develop his breathing technique, which essentially led to the development of the 13th form, which was carefully created to kill Muzan. This feat alone is remarkable and speaks to Yoriichi’s unparalleled skill. He represents the absolute pinnacle a demon slayer can achieve, showcasing not only his immense talent but also his intellect and strategic brilliance in the fight against demons.

6

Gyomei Himejima

The Strongest Hashira is also One of the Smartest Hashira

Gyomei Himejima, the strongest of Demon Slayer’s Hashira, is also the most admired character from the series after Kagay Ubyuashiki, for his innate leadership qualities and intellect. Unlike other demon slayers, Gyomei is never shown to lose his composure and showcases a calm presence throughout his battle against the demons.

Gyomei was also among the first to deduce a crucial strategy for defeating Muzan, recognizing that the demon’s survival relied on possessing multiple vital organs, all of which needed to be destroyed simultaneously. This revelation showcases his exceptional insight and quick thinking on the battlefield. However, it is tragic how Gyomei’s intellect stems from a poignant incident.

5

Shinobu Kocho

Though Shinobu Lacks Physical Prowess, She Makes Up For It By Her Intelligence

Shinobu’s initial depiction would suggest that she is lighthearted and playful among the Hashira, but her analytical mind and intelligence arguably surpass those of her peers. Shinobu clearly lacks physical prowess but makes up for it with her wit, which is evident from her breathing style. While Giyu was able to craft an additional form to his breathing style, Shinobu developed a whole breathing style to flawlessly overcome her lack of strength.

Her extensive knowledge of poisons and medicine is equally remarkable, enabling her to both kill demons efficiently and save countless lives. This expertise proved critical in the Demon Slayer’s final battle against Muzan, where her contributions not only helped in his defeat but also prevented Tanjiro from becoming a demon who could conquer the sun, solidifying her position as the smartest Hashira from the Demon Slayer.

4

Muzan Kibutsuji

Muzan Also Posses the Crucial Trait of a Shōnen Villain: Smartness

Having lived more than a thousand years, there is no doubt that Muzan is flooded with information that no other has. As the sole creator of demons and the first in series history, he has been responsible for shaping thousands of variations, each with unique abilities. His expertise extends beyond mere biology as he is also a master of chemistry, stealth, and manipulation, all of which he uses to further his goals.

With a highly strategic mind, Muzan consistently stayed one step ahead of the Demon Slayer Corps for centuries, always evading their grasp. Considering how Muzan even possesses five brains, his intellect is mathematically five times better than that of a normal human. Therefore, it is all the more satisfying to witness the end of Muzan’s reign with the power of the demon slayers, which was harnessed by thousands for centuries.

3

Tamayo

The Most Intelligent Demon

Tamayo is the only demon in the series whose intellect surpasses that of Muzan, the creator of all the Demons. Having lived for centuries, Tamayo was able to harness her scientific knowledge to a level that helped her reverse the process of becoming a demon, helping many regain their humanity and break free from Muzan’s control.

However, her profound work lies in developing the poison that severely weakened both Muzan and Doma, which is pivotal in ensuring the Demon Slayer Corps’ ultimate victory. Every one of Tamayo’s contributions highlights her unmatched intellect and her essential role in the downfall of the Demon King.

2

Kagaya Ubuyashiki

Kagaya is Intentionally Crafted to be the Smartest Character In Demon Slayer

Kagaya Ubuyashiki’s role in Demon Slayer is easily missed as he is absent from the battlefield. Still, he plays the most critical role in the series: guiding the Demon Slayers Corps against demons. He has impressive insights, which enabled him to employ the best use of demon slayers in the most critical situations to minimize losses. What sets Kagaya apart, however, is his remarkable ability to see people for who they truly are, earning him the deep respect and admiration of those he leads.

Moreover, it is revealed that Kagaya possesses the gift of foresight, a power passed down through the Ubuyashiki family. This ability to predict outcomes proved vital, as it enabled him to devise the trap that weakened Muzan at the start of the final battle. Kagaya’s unique blend of empathy, foresight, and strategic brilliance highlights that he is intentionally crafted to be the smartest character from Demon Slayer.

1

Tanjiro Kamado

The Protagonist of Demon Slayer Has Showcased Relatable Intellect Consistently

Tanjiro Kamado, the protagonist of Demon Slayer, grows increasingly strategic and intelligent as the series progresses, ultimately becoming one of Demon Slayer’s strongest characters. However, what truly distinguishes Tanjiro from others is his deep sense of maturity, a quality rarely found in someone so young. Despite being in his mid-teens, he exudes a warmth and wisdom that surpasses his years, a trait tragically forged by the loss of his family.

This maturity is most powerfully displayed early in the series when Tanjiro comforts Kazumi, who is devastated by the loss of his fiancée. While anyone could have offered words of encouragement, Tanjiro’s gentle and empathetic delivery makes his message profoundly impactful. His ability to console and inspire others, even in the face of his own suffering, sets him apart. Combined with his growing battle intellect, adaptability, and compassionate nature, Tanjiro Kamado stands out as one of the smartest and most emotionally intelligent characters in Demon Slayer.