Nezuko Kamado

Nezuko Kamado is Tanjiro's younger sister. She was turned into a Demon by Muzan Kibutsuji. She travels alongside her brother on his quest to turn her human again.

Appearance
Nezuko has long black hair which she tied into a bun as a human but wears loose as a demon. It is decorated with several small, light pink ribbons. As a demon, her black hair fades to orange near the bottom. Her eyes are bright pink, but were formerly a deep red as a human. She carries a piece of bamboo in her mouth, which is bound by a red tie.

She wears a pink kimono with a star pattern, a red and white checkered obi, and a black haori. On her feet and legs, she wears pink zori sandals, white socks, and black leg wraps.

She was known to be a great beauty in her home village.

As a demon, she can change the size of her body. She has also gained sharp fangs, claw-like nails, and slit pupils as a result of becoming a demon.

Personality
Nezuko's original personality as a human was that of a kind and caring girl, who thought of others before herself much like her older brother Tanjiro. She was a responsible elder sister to her younger siblings.

As a demon, Nezuko seems to have forgotten a good portion of her memories as a human, besides those related to her family. She is still very caring and protective towards other humans who she sees as members of her family due to Urokodaki's influence while she was asleep for two years. She is also rather brazen, and does not seem to fear fighting; she fiercely guards her brother as well as her allies.

She still retains her human emotions, as she has been seen to cry and be happy, but in general she appears more detached than her human cohorts, as well as calmer and less malicious than most demons.

As a demon, Nezuko does not talk often and stutters a lot. This may be due to her bamboo mouthpiece, which is seldom removed. It also means she is sometimes hard to read.

History
Nezuko grew up on a mountain alongside her older brother, Tanjiro, and the rest of her siblings and mother. She is the eldest daughter of the Kamado family. She presumably took care of her younger siblings as an assistant to her mother, as is briefly witnessed prior to her family's death. Unlike Tanjiro, who was responsible for selling firewood in town, Nezuko would usually help out around the family home.

The family was somewhat poor and as a result, Nezuko sometimes had to go without things like new clothes in order to ensure that the rest of her siblings had enough food to eat. She did not appear to view this as a burden, and instead was content to help her family.

After a demon killed her family aside from Tanjiro, Nezuko was turned into a demon as a result of the attack. At first, she was rather wild and even attacked her single remaining brother. However, she quickly came to her senses and defended him from Giyuu. Since then, she has traveled with her brother in order to find a way to become human once again.

Demon Abilities
Ability to Change her Body Size: Ever since Nezuko was turned into a Demon, she can change the size of her body at will. She usually turns smaller to fit herself inside basket / box, and turns Larger to battling Demons.

Enhanced Strength: Nezuko can fight and defend herself from Demon attacks, and she occasionally uses her legs to kick open doors. Her kicking power depends of her body size, and her kicks also able to sever Demons head with ease.

Regeneration: Nezuko possesses a tremendous regeneration ability that able to restore severed limbs within seconds. The true nature of this ability is solidifying her blood from her severed body parts that she could manipulate at will.

Rage Empowerment: When Nezuko is under the dire situation, she could transform into a berserk-like state, with vines tattoos circling her body, her veins popping out and a single horn protruding from her right forehead side. This form enhances Nezuko fighting ability, at the cost of her becoming more demon-like, including the need to feed on humans blood. So far, the only way she could revert back to normal is to have someone (in her case, Tanjiro) sing her a lullaby. During the demon slayers fight against Hantengu, Nezuko manages to control this form at will.

Sunlight Resistance: For some reason, Nezuko obtained a body which did not burn under sunlight, unlike other demons. However, this resistance isn't perfect as she still prefers to avoid sunlight, given the way she hides from it and has Tanjiro carry her around during the day.

Blood Demon Technique
 * Blood Burst - Nezuko causes her blood to ignite with hot flames instantly. Nezuko could control the temperature of her flames to either non-lethal (as shown when she forcefully wakes Tanjirou during the Demon Train incident) to lethal at will. Nezuko flames also able to turn Tanjirou Nichirin Blade from jet Black to Crimson Red, similar to Tanjirou ancestor blade, strengthening the blade even further and allows Tanjirou to perform Dance of the Fire God styles more effectively.

Trivia

 * Kamado, without the second kanji (竈, かまど) is a traditional Japanese wood or charcoal-fueled cook stove/furnace.
 * Do, the second kanji of her family name, (門, ど) means door.
 * Nezu (禰豆, ねず) is part of the word Gonezu (五禰豆, ごねず), which is the name of a flower, the Japanese Snowball.
 * Ko (子, こ) is a common Japanese name suffix for girls. It also means child.