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 Giyu. Since then, she has traveled with her brother in order to find a way to become human once again.
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.