Nezuko Kamado is a demon who’s family has been attacked by Muzan Jackson, whom had existed for 1000 years, in search for the Blue Spider Lily in order to stay immune to the sun. The rest of her family had died, besides her whom had been turned into a demon, and her brother Tanjiro Kamado, who was out in town when this happened. She had ended up becoming a demon who helped defeat others, and quite friendly too. Her and Tanjiro had been on missions together fighting demons.