Zo is Lia's younger sister. Although before the accident Zo wanted nothing to do with Lia's friends or lifestyle, when Lia returns to school after rehab she finds that Zo has taken her place as the leader of her friends, has taken her spot on the track team, and has even taken her boyfriend Walker. Zo is consumed with guilt because she blames herself for Lia's accident, and has taken her place everywhere because she believes that the downloaded Lia is just a copy of her sister and not really Lia at all. Zo believes that Lia is dead because of her, and she will not allow a machine to take her sister's place.