Inosuke is a young man of average height with a pale complexion and an exceptionally toned, muscular build for his age. Despite his rugged physique, he possesses a surprisingly feminine and pretty face, characterized by large, wide eyes framed by long lashes, with irises that range from dark to soft pale green. His thin eyebrows and small, delicate mouth further contrast with his rough personality. Inosuke’s thick, raven-black hair reaches just past his shoulders, fading into blue at the tips. It forms an unruly fringe that puffs out before curving towards his forehead.

Inosuke’s attire is a customized version of the standard Demon Slayer uniform, modified to match his unique style. He wears baggy hakama pants in a dark gray-blue shade, secured with a belt decorated with fluffy brown deer fur. Unlike his fellow Demon Slayers, he does not wear a haori. Instead of the usual leg wraps, Inosuke opts for knee-high socks made of bear hide, which serve as a base for his sandals, leaving his heels and toes exposed. His most defining feature is the hollowed-out boar’s head that he wears as a mask. Inosuke has altered the boar’s head to include eye holes, allowing him to see while wearing it.

Inosuke is short-tempered, confrontational, and abrasive. He is fiercely proud and constantly views himself as the strongest fighter in any situation. This attitude often leads him to challenge nearly everyone he meets, craving respect and praise for his skills. His bravado frequently lands him in unnecessary danger, as he tends to overestimate his abilities against his opponents. This was evident when Giyu Tomioka had to restrain him after a fight with the Father demon to prevent him from recklessly challenging the Hashira while still severely injured. His desire to be the best also makes him provocative, frequently attempting to goad others, especially Tanjiro Kamado, into fighting him, though Tanjiro’s kind nature often foils these attempts.

Inosuke has a vengeful streak, especially when those he cares about are harmed. He initially refused to help an injured train engineer who had attacked Tanjiro, only assisting after Tanjiro begged and forgave the man. His fury was also directed at Doma after learning he killed and devoured Shinobu, attacking the Upper Rank demon and vowing to create hell for him. When he discovered Doma was responsible for orphaning him, Inosuke’s anger intensified. Additionally, he directly challenged Muzan Kibutsuji, demanding the demon atone for maiming and killing his fellow Demon Slayers.

Having been raised by boars, Inosuke initially lacks basic social understanding. He often assumes that anyone approaching him intends to attack and struggles to comprehend kindness. He cannot read or write and frequently mispronounces names, calling Tanjiro “Monchiro” and Zenitsu “Monitsu.” His initial rudeness and tendency to view everyone as an enemy are unintentional byproducts of his upbringing.

As the story progresses, Inosuke is increasingly influenced by Tanjiro’s compassionate nature, becoming more accustomed to affection and generosity. He learns to acknowledge the strength of others besides himself and develops a sense of friendship toward both Tanjiro and Zenitsu. Despite retaining his proud nature and desire for praise, Inosuke begins to think more strategically during battles, adopting tactics learned from more experienced Demon Slayers rather than rushing in recklessly. His sense of camaraderie grows, exemplified when he confronts Muzan Kibutsuji, mourning the fallen Demon Slayers and demanding the Demon King return what he has taken or die for his crimes.

• Animal Imitation:

  Growing up with wild boars in the mountains, Inosuke adopted their habits, incorporating them into his combat style. His fighting approach, both in hand-to-hand combat and swordsmanship, is reminiscent of animals and beasts. Tanjiro Kamado noted that Inosuke’s unorthodox movements and low-angle attacks make his style similar to that of a “four-legged beast,” adding an element of unpredictability and ferocity to his battles.

• Indomitable Will:

  Inosuke possesses an unwavering will and spirit, remaining fearless and steadfast against any foe, often to the point of endangering himself. His determination was most evident during his battle against Upper Rank Two, Doma. Despite sustaining numerous injuries, he refused to give up, continuing to fight against Doma’s overwhelming power. Even when facing the Demon King, Muzan Kibutsuji, Inosuke remained resolute and unyielding.

• Poison Resistance:

  Inosuke has shown resistance to poison, surviving the effects of Upper Rank Six, Gyutaro’s deadly venom, suggesting a degree of immunity to certain toxic substances. However, as noted by Aoi Kanzaki, this resistance means that none of Shinobu Kocho’s medicines can work on him. Therefore, if exposed to a stronger or unfamiliar poison than that of Gyutaro’s, Inosuke could face a greater risk of death, as remedies would not be effective.

• Enhanced Flexibility:

  Inosuke possesses extraordinary flexibility, capable of bending his body to extreme degrees, such as arching backward until his head touches between his feet. He can also dislocate and relocate his joints at will to extend his reach or adapt to combat situations. This flexibility extends to his internal organs, as demonstrated during the battle with Daki and Gyutaro, when he shifted his heart to avoid a fatal blow.

• Immense Speed & Reflexes:

  Inosuke is incredibly fast and agile, able to dodge attacks in high-speed combat scenarios, such as Kyogai’s air slashes, and outmaneuver multiple enemies. His reflexes allowed him to keep up with Upper Rank demons, including Daki and later Doma. Inosuke was able to attack and land hits on Doma and even steal a sword from him undetected. His speed was also sufficient to fight on par with Muzan and a transformed Tanjiro, even when severely injured.

• Immense Stamina & Endurance:

  Inosuke’s endurance is exceptional, as shown when he continued to fight despite broken ribs and survived direct attacks from powerful demons like Father and Daki. Even after being poisoned and stabbed, Inosuke remained active in battle. He withstood numerous blows from Doma and continued to fight Muzan despite accumulating many injuries, showing his impressive resilience.

• Immense Strength:

  Inosuke possesses superhuman strength, allowing him to dual-wield two katanas and use them with enough force to create air slashes. He has demonstrated feats of strength such as lifting Tanjiro and another Demon Slayer with ease, breaking through the Mugen Train’s roof, and moving a boulder with his bare hands. His physical prowess enabled him to damage Doma and drive a sword through his neck during their battle.

• Repetitive Action:

  Inosuke masters this technique, which allows a Demon Slayer to achieve the effects of Total Concentration Breathing through repetitive movements or recalling intense emotions. By doing so, the user opens their five senses and elevates their concentration, drawing out their physical strength for an extended period. Repetitive Action can be used alongside Total Concentration Breathing, granting immense strength that can rival Upper Rank demons. Inosuke mastered this ability after observing Tanjiro and uses his personal mantra, “Boar Rush!”, to help maintain focus while using it.

• Enhanced Touch:

  Inosuke developed an exceptionally sharp sense of touch from growing up in the mountains, allowing him to detect even the slightest vibrations in the air. He incorporated this ability into his Spatial Awareness technique, enabling him to sense demons’ locations over vast areas and detect hostile intentions directed toward him. This ability gave him an edge in combat, allowing him to preemptively react to threats. During his battle against Doma, his heightened sense of touch also helped him avoid inhaling dangerous frost, showcasing the practicality of this skill in life-threatening situations.

• Extrasensory Perception:

  Inosuke’s heightened senses are so advanced that they grant him a form of extrasensory perception, allowing him to detect things beyond normal human capabilities. He can sense the seriousness of his opponents’ attacks, as demonstrated when he noticed a slight relaxation in Daki’s sash movements, giving him an opportunity to strike. Inosuke can also perceive malice and killing intent from others, even when they are out of his line of sight, which helped him avoid fatal attacks like Gyutaro’s scythe strike. Additionally, his ability allowed him to detect the presence of living people trapped inside Daki’s obi, preventing him from causing them harm during battle.