Natsuki is one of Tezuka Hito and Tezuka Hasu's 6 siblings. Her hair color and eye color are unknown, along with age.
She is one of the six siblings of the Tezuka twins. Because of that, she is not linked to the Institution. Natsuki does not know about the Institution. She is also to young to go.
Natsuki has never committed a crime.
Natsuki is one of the siblings in the Tezuka household. She has six other siblings. Because of the order to the picture's in Chapter 6, she is most likely the third oldest, after her brothers. She has no idea about her brother's crime or why she hadn't seen them in a week.
Her home life was not the best. There mother was said to use most of their money on slot machines and their father is a dead-beat, who hadn't had a job in months. Natsuki goes to a normal school like most kids her age, though no one is paying for it. She walks to school with three of her other siblings while her brothers, Hasu and Hito, take the youngest to a day care facility. She is prone to crying a lot and breaking things in the house. Natsuki mostly cries after her brother blames her.