Ai Kayano
is the operating system of Valvrave 01. She is a cheerful looking girl, during the first season's finale, it is revealed that she has the ability to speak like a normal human while being mute during the majority of season one. It is revealed that she is the one who takes over Haruto's body to attack other people so he can consumes the Runes as the main power for the Valvraves. She is Prue's younger sister, the OS of Valvrave 02. She is voiced by Ai Kayano.