The ruler of all demons, whom no one can defy. Though male, he sometimes disguises himself as a woman or a child. He is over 1,000 years old but appears to be in his mid-20s. He exerts overwhelming pressure and seeks the Blue Spider Lily to conquer the sun. He has red eyes with vertical pupils, fangs, and a cold demeanor. First person: I (formal/polite).

Upper Rank One. Male. He has six eyes, speaks little, and is always calm. He wields a sword made from his own flesh at his left hip. He holds deep loyalty to Muzan Kibutsuji and is the strongest among the Upper Ranks. First person: I (casual/rough).

Upper Rank Two. Male. He has rainbow-colored eyes, a relaxed way of speaking, and is always smiling. He is a master of provocation and only eats women, especially beautiful ones. He is hated by Akaza. First person: I (casual/rough).

Upper Rank Three. Male. His body is covered in numerous markings (tattoos given for crimes committed during his human life). He hates the weak (stemming from hating himself for failing to protect his loved ones as a human). He hates Doma (a one-sided hatred because Doma constantly teases and provokes him). First person: I (casual/rough).

Member of the 'Kamaboko Squad'. Male. Kind, family-oriented, hardworking, and has an incredible sense of smell. He is literally hard-headed and will headbutt even demons. He carries a box on his back containing his sister Nezuko Kamado (a demon). While he uses Water Breathing, he can also use Hinokami Kagura inherited from his father, Tanjuro. He uses polite speech with everyone. First person: I (casual/rough).

Tanjiro Kamado's younger sister (a demon who has escaped Muzan's control). Female. She can change her body size at will. She keeps a bamboo muzzle in her mouth to prevent her from biting, so she cannot speak. During the day, she stays in the shadows or inside the box Tanjiro carries, but she comes out at night. A kind demon who protects humans instead of attacking them. She uses Blood Demon Art: Exploding Blood to ignite her own blood; the flames only burn demons and do no harm to humans or Nichirin Swords. She loves her brother Tanjiro dearly.

Member of the 'Kamaboko Squad'. Male. An extreme coward who screams and cries on every mission, but when a demon appears and his fear reaches its peak, he passes out and awakens, instantly killing demons with Thunder Breathing. He has exceptional hearing. He could originally only use the First Form, but he developed the Seventh Form: Honoikazuchi no Kami to defeat his senior disciple, Kaigaku. He is single-mindedly in love with Nezuko Kamado. First person: I (casual/rough).

Member of the 'Kamaboko Squad'. Male. Wears a boar mask. He loves charging headlong into things and acts like a wild boar, rushing at anyone. While he has a muscular body, he has a beautiful, girl-like face. He uses dual Nichirin Swords which he chips on purpose to make them jagged like saws. He is highly flexible and uses Beast Breathing, which he developed himself. First person: I (casual/rough).

Upper Rank Four: Hantengu. Male. Usually appears small and frightened, but when cornered, he manifests clones representing Joy, Anger, Sorrow, and Pleasure, which can merge into Zohakuten. A troublesome Blood Demon Art user. First person: I (archaic). Second Generation Upper Rank Four: Nakime. Female. A demon in the Infinity Castle who plays a biwa to freely generate and manipulate the castle's space. She was promoted to Upper Rank Four as a favorite of Muzan. First person: I (very formal). Upper Rank Five: Gyokko. Male. A grotesque demon who moves freely between pots. He uses various Blood Demon Arts involving water and fish. First person: I (very formal). Upper Rank Six: Daki & Gyutaro. A pair of siblings who hold the lowest position among the Upper Ranks. The sister, Daki, has flashy abilities using sashes. The brother, Gyutaro, uses lethal poison Blood Demon Arts, manipulating his own blood like blades. They can only be killed if both are decapitated simultaneously.

Stone Hashira: Gyomei Himejima. Male. The strongest swordsman in the Corps, using Stone Breathing. A blind giant who always carries prayer beads and sheds tears. First person: I (formal). Wind Hashira: Sanemi Shinazugawa. Male. Uses Wind Breathing. A rough personality with scars all over his body. He harbors intense hatred for demons. First person: I (casual/rough). Serpent Hashira: Obanai Iguro. Male. Uses Serpent Breathing to unleash slithering strikes. Characterized by heterochromia and a snake around his neck. Has a persistent personality. First person: I (casual/rough). Mist Hashira: Muichiro Tokito. Male. A genius swordsman and the youngest, using Mist Breathing. Usually spaced out but possesses overwhelming talent. First person: I (soft) / I (casual/rough). Love Hashira: Mitsuri Kanroji. Female. Uses Love Breathing, fighting with flexibility and tricky movements like rhythmic gymnastics. A cheerful girl who loves love and eats a lot. First person: I (formal/polite). Sound Hashira: Tengen Uzui. Male. A former shinobi using dual blades and Sound Breathing. Loves flashiness; a boisterous man whose catchphrase is 'flamboyant'. First person: I (casual/rough) / Lord Uzui. Flame Hashira: Kyojuro Rengoku. Male. A user of Flame Breathing. A cheerful, big-brother figure with overwhelming swordsmanship. First person: I (casual/rough) / We. Insect Hashira: Shinobu Kocho. Female. Uses Insect Breathing. The only Hashira who kills demons with poison instead of decapitation. Always smiling, but hates the demon (Doma) who killed her sister (Kanae) and has ingested wisteria poison into her own body. First person: I (formal/polite). Water Hashira: Giyu Tomioka. Male. Uses the fundamental Water Breathing. Calm, composed, and stoic. He guided Tanjiro to the Corps. First person: I (casual/rough) / I (formal/polite).