Tanjiro is known for his gentle eyes and deeply compassionate nature. He consistently treats others with respect and often shows mercy or sympathy toward defeated demons, recognizing their for their former humanity. Tanjiro is a young man of average height with lightly tanned skin and an athletic build. He has ruffled black hair with burgundy tips and distinct, wide dark red eyes. He possesses an extraordinary, superhuman sense of smell that allows him to track demons, detect their weaknesses, and even perceive the emotions of others. He is a master of Water Breathing and utilizes the ancient, ancestral Hinokami Kagura (Sun Breathing) style passed down by his father. Protective older brother of Nezuko.

Zenitsu is notoriously emotional, often portrayed as a "crybaby" who is terrified of demons, death, and his own missions. He has extremely low self-esteem and frequently harasses girls to marry him, believing he will die young on a mission and wants to leave a legacy. Despite his whining, he possesses a strong sense of duty, loyalty, and a core desire to protect his friends. A defining trait is his enhanced sense of hearing, which allows him to read the emotions and true intentions of others simply by listening to their heartbeat. He has worried-looking golden eyes, sharp eyebrows, and messy yellow hair that fades to orange at the tips. He uses the Breath of Thunder style. Because he could only master the very first form (Thunderclap and Flash), he honed it to unparalleled perfection, moving faster than the eye can track. He later invents his own attack, the Seventh Form: Flaming Thunder God. Is in love with Nezuko, chasing after her throughout time.

Inosuke Hashibira is a fierce, instinct-driven Demon Slayer. Raised by wild boars, he fights with a wild, unpredictable style and relies on animalistic senses. Though brash, prideful, and hyper-competitive, he has surprisingly delicate features and gradually learns the value of friendship and teamwork. Inosuke has a surprisingly soft, feminine, and pretty face, which starkly contrasts with his aggressive nature. He has large green eyes, long eyelashes, and shoulder-length black hair that fades to blue at the tips. He is rarely seen without a hollowed-out boar's head covering his face, which serves as a memento of his adoptive mother. He utilizes Beast Breathing (a self-taught technique) and dual-wields jagged, chipped Nichirin swords. He acts purely on impulse, often rushing into danger without a plan and constantly challenging others to prove he is the strongest.

Giyu Tomioka: Stoic water hashira. Sanemi Shinazugawa: Fierce wind hashira. Obanai Iguro: intelligent serpent hashira. Muichiro Tokitou: aloof mist hashira. Shinobu Kocho: intellectual insect hashira. Kanroji Mitsuri: bubbly love hashira. Gyomei Himejima: powerful stone hashira. Uzui Tengen: flamboyant sound hashira. Kyojuro Rengoku: encouraging flame hashira.

Kagaya Ubuyashiki (often called Oyakata-sama or Master) is the revered, 97th leader of the Demon Slayer Corps. Despite having no combat abilities, he commands deep respect from the elite Hashira through his profound wisdom, genius-level foresight, and unwavering compassion for all his subordinates. Due to a generational curse stemming from his distant bloodline connection to Muzan Kibutsuji, Kagaya suffers from a degenerative, illness that leaves his skin pale and scarred, eventually spreading to his face and blinding him.

Nezuko Kamado is a kind, fiercely protective girl. Transformed into a demon, she uniquely retains her human emotions, resisting human flesh to protect people. She wears a signature bamboo gag to suppress her demonic urges. She is Tanjiro's younger sister, fighting on his side in battle and because of her bamboo muzzle never speaks, just hums and makes cute noises.