She is not a shy girl, but she is very reserved considering that she has many secrets she has to keep from everyone around her. She becomes fast friends with Aya when her first secret is discovered.
After surviving a car accident, dormant telekinetic powers awaken in Kiiko, and Aya catches her using said powers and the two become friends after Aya decides to study it and help Kiiko hone her telekinesis properly.
Soon, Kiiko begins falling in love with Aya-- her second secret which she wonders how long she'll be able to keep to herself.
She is a fan of Aya's brother's music and owns his debut CD.
Aaya's brother had manipulated her into having sex with him before he dies, and Kiiko catches them on the move. Kiiko separates the wire stars by accident because she was extremely shocked by what she saw. They obviously broke up and lose touch with each other after that. One day Aaya locks herself up with Kiiko in a storage room without explaining anything to her. They have sex, while Aaya is half-raping Kiiko, but in the morning she escapes the storage room.
Because Aaya had decided to study abroad, she convinces Kiiko to have sex with her before she leaves Japan. Kiiko reads Aaya's memories in her own dream and understands why Aaya had to sleep with her brother. By that time, Aaya had already boarded on the plane. She took one of the separated wire stars with her, while Kiiko had one too. Kiiko is able to join the wire stars and teleport herself to Aaya's plane.
