Kei

She is a genius cyberdoll said to have an IQ of 50000 in human terms. Kei is originally given the mission of formulating a strategy to get May back. She becomes interested in Kazuya after hearing how he regards cyberdolls and changes her mind. Keis memory bank of facts is extensive but she often takes a while to process information that is more abstract. At times abstract or philosophical questions can cause her CPU to lock up. Source: Wikipedia