Sumi Nakahara (中なか原はら すみ Nakahara Sumi?) is a servant of the Butterfly Mansion.
Sumi has light skin and a set of black, button-like eyes. She wears her hair in low twintails fastened with blue butterfly clips.
She sports a long-sleeved nurse uniform tied with a blue ribbon around her waist and wears white socks and shoes.
Like the other members of the trio, she is very bright cheery and helpful.
After her family had been killed by Demons, Sumi was taken in by the Butterfly Mansion.
Yushiro (愈ゆ史し郎ろう Yushirō?) is the traveling companion of Tamayo and a close ally of Tanjiro Kamado. He was turned into a Demon by Tamayo.
Yushiro has the appearance of a young boy with pale skin and bright lavender purple eyes. He has short hair that is neatly styled and vertically shaded from a dull green to black. Yushiro wears a button-up shirt under an all-white kimono and dark blue pants.
Yushiro was a human who was under the care of Tamayo as she was practicing as a medical practitioner. He was in frail state fighting a disease when Tamayo gave him the choice of succumbing to his illness or to live longer as a Demon. He agreed to become a Demon and has since stayed by Tamayo's side serving as an assistant as well as her guard.
