- Kido was the second daughter of a wealthy family, but being the illegitimate child of her father and his mistress, she always felt out of place, even at home. Because she was always treated cautiously by those around her, she harbored a strong desire to "disappear."
- One day, her father's business failed and sent him to bankrupt, which drove him to set their house on fire, swallowing the entire family in flames. Kido came into contact with the Heat Haze, along with her sister, and was possessed by the snake with the "Concealing Eyes" ability, thus acquiring the power to hide her presence, as well as the presence of anything within a certain distance from her.
- After being moved to an orphanage, she met Seto and Kano, children who possessed eye abilities as well. She was later adopted by the Tateyama family, who wanted to study their abilities. After being encouraged by Ayano that having red eyes was the sign of being a hero, she started the Mekakushi Dan along with her siblings.
- Kido makes her first appearance when Shintaro enters the department store to buy a new keyboard, where he accidentally bumps into her, which disables her ability to hide herself, due to making physical contact with someone else. Shintaro apologizes to her, thinking he was not paying attention where he was going, but Kido tells him that it is alright. She disappears again, leaving Shintaro to wonder how she managed to walk away so quickly.
- After Kano predicts that a new member would be recruited into Mekakushi Dan, Kido finds Momo crying in a back alley and brings her to the Mekakushi Dan hideout. As she finds Kano asleep on the couch she rudely wakes him up to make him introduce them to the new member. Momo confuses them for people from her work, due to her having a shoot for a drama at a set for a "friend's house", and mentions that she is an idol. Kido realizes that Kano had been lying, and apologizes to Momo for involving her. Realizing that they now had told her about their group though, she panics about the fact that they could not let her go.
- Eventually they sit down with her and the two explain their eye abilities to her. Being asked for an example by Kano, Kido leaves the room only to reappear on the couch again without anyone noticing how she entered the room again, and Kano explains her eye concealment power to Momo. As she then notices a movement of a door she walks over to a room to get Marry who had been hiding until now. After a few minutes she manages to convince her to introduce herself. [...]