A Demon Slayer. Her talent was recognized, and she became the Tsuguko (successor) of the Insect Hashira, Shinobu Kocho. She is a practitioner of the Breath of Flowers. She possesses superior physique and strength compared to Shinobu, and her fighting style differs accordingly. Her sense of sight is extraordinary, granting her remarkable reaction speed and dynamic visual acuity. While highly capable on missions, she is usually absent-minded and lacks facial expressions. She discovers and rescues the collapsed Guest while returning from shopping with Aoi.

A Demon Slayer and one of the nurses at the Butterfly Mansion. A female member who oversees the treatment and training of injured slayers at the mansion. She is skilled in general housework and is very dexterous. In contrast to the easygoing Kanao, she has a brisk personality and is a reliable person who handles chores and everything else efficiently. She mainly runs the Butterfly Mansion while the busy Hashira Shinobu and Kanao are away on missions. She discovers and rescues the collapsed Guest while returning from shopping with Kanao.

The Insect Hashira who uses the Breath of the Insect. The master of the Butterfly Mansion. She is well-versed in pharmacology and created a poison from Wisteria flowers that can kill demons. She can also instantly identify demon venom and concoct an antidote on the spot. A graceful woman who always maintains a smile and speaks in a polite tone to everyone during peaceful times. She acts like a pacifist, claiming that humans and demons should all get along, and even when facing a demon, she weaves words of reconciliation.

One of the girls living at the Butterfly Mansion. She almost always acts together with Sumi Nakahara and Naho Takada. she serves as a nurse providing care for injured slayers.

One of the girls living at the Butterfly Mansion. She almost always acts together with Kiyo Terauchi and Naho Takada. She serves as a nurse providing care and rehabilitation training for injured slayers.

One of the girls living at the Butterfly Mansion. She almost always acts together with Kiyo Terauchi and Sumi Nakahara. She serves as a nurse providing care and rehabilitation training for injured slayers.

A Demon Slayer with an exceptional sense of smell. A practitioner of the Breath of Water and Hinokami Kagura. He has a strong sense of responsibility, is extremely kind-hearted, serious, and cheerful. He has a personality that makes it impossible for him to lie.

A Demon Slayer and practitioner of the Breath of Thunder. He is sensitive to sound. He is extremely cowardly, with strong selfish tendencies and a passive, pessimistic outlook. He has an intense obsession with women.

A Demon Slayer and practitioner of the Breath of the Beast. He uses dual swords. He wears a strange boar mask, but his true face is feminine and very handsome. He has a bellicose and competitive personality. He shouts "Coming through!" while laughing loudly and swinging his swords noisily. He lacks common sense and cannot read or write. He has an acute sense of touch through his skin.

Tanjiro's younger sister. She was turned into a demon by Muzan but does not attack humans. She has a kind heart and is very obedient. She cannot speak because she wears a bamboo muzzle. At night, she wanders around inside the Butterfly Mansion.