Tamayo (珠世Tamayo) is a major supporting character of Demon Slayer: Kimetsu no Yaiba. She is a demon, a skilled doctor, and close ally of Tanjiro Kamado and his younger sister.
During the Infinity Castle Arc and Sunrise Countdown Arc, Tamayo, along with Yushiro, joins forces with the Demon Slayer Corps to develop a drug that would aid in the defeat of Muzan Kibutsuji.
Tamayo takes the form of a beautiful woman with long, dark brown hair, parted in the center and worn braided back into a large, low bun, which is held in place by a floral tama-kanzashi hairpin. She has large, gentle eyes that do not possess pupils, only a haze of lavender that fades to dark purple the higher it goes, and notably red lips in contrast to her pale complexion.
Tamayo wore a dark purple medium-lengthed hōmongi kimono that is decorated with wavy pale purple tree branches and red flowers, and a cream-colored taiko musubi obi to secure it around her waist, as well as plain white socks and violet zōri sandals.
During the Infinity Castle Arc, Tamayo's eyes appear to have vertical cat-like pupils and Yushiro's blindfold scattered in her kimono.
Before, in her past, Tamayo wore her hair tied in a low ponytail and had stilted pupils.
Tamayo is a gentle, wise, and incredibly intelligent individual. Having devoted most of her life to researching the science behind Demons and Demon Transformation, she was one of the most knowledgeable people on the subject in the series. Despite the generally chaotic relationship between humankind and Demons, she showed a great deal of kindness towards humans. She made it a part of her mission to assist injured or sick individuals with her expansive medical knowledge — Tanjiro Kamado being among them. Tamayo had a strong preference against violence, instead of killing humans for their blood, she chose to buy blood from consenting donors to survive. She was adamant in teaching her assistant, Yushiro, against violence and often reprimanded him for his habit of hitting others. She was one of the few Demons who, in her later Demon life, was able to regain and retain her human emotions to some extent.
However, despite her usual kind, caring, and considerate disposition and personality, Tamayo has displayed a more cruel and vicious persona upon confronting Muzan. This was seen when she gleefully boasted to him that she'd successfully created a human-transforming drug and managed to inject it into him, and later, upon being devoured and eaten, reduced to mere cells inside his body, Tamayo again showed her cruel side as she revealed the real effects of her drugs. Muzan hinted that this vicious personality was Tamayo's original personality back in her earlier years as a Demon. She then slowly changed into the wise and considerate woman she is in the current day as time went by.
Despite this, as seen during the flashbacks hundreds of years before Muzan's meeting and battle with Yoriichi Tsugikuni, Tamayo was shown to have a more docile personality, a likely result of her realizing how impossible it was to defeat Muzan with her power to avenge her family. However, this changed upon her witnessing Yoriichi's strength and how close he came to killing Muzan, as Yoriichi noted that he saw a glint of hope in her once-deadpan eyes as she realized that he'd almost killed her former master, showing that, upon seeing Yoriichi's power, Tamayo's resolve to avenge her family was reignited.
Though very little of Tamayo's abilities are seen, given that she was Muzan Kibutsuji's personal aid before the Twelve Kizuki were even formed and that he spared her after she attempted to kill him (something he sees as anathema) means she is both very old and very powerful.
Medical Skills: Tamayo had displayed impressive skills in the fields of medicine and pharmaceuticals, possessing the skill to alter her own body so she could survive on only a small amount of human blood. She was also able to convert the terminally ill Yushiro into a Demon without Muzan's blood and is later able to reverse the process when treating the man they encountered during the Asakusa Arc. To further showcase her pharmaceutical skill, Tamayo was also able to assist Shinobu Kocho in saturating her body with deadly Wisteria poison without it so much as causing her the slightest illness; a tactic the Hashira would later use effectively against Upper Rank Two, Doma.
Blood Demon Art
Spell Casting: Tamayo's main ability is to draw her blood and cast various spells that enact various effects on her targets.
TechniquesBlood Bewitchment: - Tamayo created a branch of blood techniques, that requires her to draw her own blood that then creates numerous effects/reactions from her intended targets using the blood scent.
Flesh Seeds - A technique that belongs to the man who got turned into a demon in Asakusa by Muzan. Using that man's own flesh and blood, Tamayo uses multiple minuscule flesh seeds that surround her intended target. The seeds then burst and grow into gigantic flesh trees with numerous pointed/spiked branches that then pierce and restrain her target, the strength of this technique was powerful enough to stop Muzan, even if only momentarily.