1 Muzan Kibutsuji The Demon King Muzan Kibutsuji has seven hearts and five brains, making him one of the most intelligent characters in the Demon Slayer anime series.
1) Shinobu Kocho
The Insect Pillar of Demon Slayer Corps, Shinobu is undeniably the smartest individual.
Senku Ishigami is believed to possess an IQ of 180 to 200, making him a highly gifted being. He holds a profound knowledge of chemistry, mathematics, physics, biology, and all other subjects. Using his wide sense of knowledge, Senku has proved himself to be the savior of humanity multiple times.
Tanjiro has 1000 IQ | Demon Slayer Season 3 Episode 4 in Hindi - YouTube.
This life has also given him great intelligence and ability to think tactically. Muzan is a quick-thinker and strategist who is able to deal with unfavorable situations rapidly and quite well, though this may also be because the loss of his subordinates means nothing to him in the long run.
Abilities. Demon Body: Unique from other demons, he possesses seven hearts, and five brains. These are responsible for his powerful vitality, should any of them be harmed, he will be severely weakened.
The warrior Muzan feared was a swordsman named Yoriichi Tsugikuni. Yoriichi was the only slayer before Tanjiro who came close to killing Muzan, and the flashback of their fight occurred in Chapter 187.
6. L Lawliet (IQ 211) L Lawliet or 'L' in short was the only guy in the entire Death Note series who knew about the real identity of Kira. Through his keen intelligence, L succeeded in pulling Kira to a corner such that Kira was forced to play his special card to eliminate him.
This tone-deaf nature never really posed a major challenge to him during his battles, so perhaps it's not really that big a deal that he lacks this talent.
Sanemi's blood is known to be enticing yet intoxicating to Demons, which he used to bait and stab Nezuko. Sanemi is clearly the least popular Hashira among Demon Slayer fans.
85 to 114: Average intelligence. 115 to 129: Above average or bright. 130 to 144: Moderately gifted. 145 to 159: Highly gifted.
Rishi Shiv Prasanna
8-year-old Prasanna has a certified IQ of 180 which is way higher than the usual benchmark of 85-115. His score of 180 is 20 points greater than the IQ of Einstein and Stephen Fleming. Both had an IQ of 160.
Kim Ung-Yong: IQ 200–210
Somehow, Kim Ung-Yong has been dubbed both a “failed genius” and the person with the highest IQ of all time. The truth depends on who you ask—similar to his IQ score, which ranges from 200 to 210, depending on the test.
Shinobu Kocho is a capable Demon Slayer whose worthy of being the Insect Hashira. That being said, she's arguably the weakest Hashira when it comes to pure strength.
After the battle, Tanjiro returns home with his sister and friends. Later it is revealed that he married fellow slayer Kanao Tsuyuri.
Tanjuro Kamado was the name of Tanjiro Kamado's father. He passed away before the event of the main story of the Demon Slayer. It is not mentioned how long Tanjuro had passed before the story, but in several flashback scenes, we can see him interacting with a younger Tanjiro.
Working together, both Demon Slayers managed to fend off the strongest demon to have ever lived who was casually fighting them, though Tanjiro ends up losing an eye and is severely poisoned as a result, nearly causing him to lose his life.
110 - 119 is "superior intelligence", while 90 - 109 is "normal or average intelligence". An IQ between 80 and 89 suggests "dullness", while a score of 70 to 79 is classed as "borderline deficiency".
For example, on The Wechsler Adult Intelligence Scale and the Stanford-Binet test, scores that fall between 90 and 109 are considered average IQ scores. On these same tests, scores that fall between 110 and 119 are considered high average IQ scores. Scores between 80 and 89 are classified as low average.
Haruka Shiraishi: Muzan's Daughter.
Yet an official Demon Slayer "fanbook," written by the manga's creator, Koyoharu Gotouge, revealed Muzan doesn't really like Upper Rank Two demon, Doma. As Lower Ranks Six, Four, Three and Two can attest, Muzan is not averse to eliminating demons he doesn't care for, even if they're Kizuki.
Since Muzan favored Gyutaro so much, he chose to incorporate the latter's sister Daki as well. The demon king believed that she was the only tool that could be used to control Gyutaro.