|Japanese name||Ichijou Mikumo|
|Age||AAI:ME: 17 (10 in flashback case)|
|Family||Father: Byrne Faraday|
Kay is a teenage girl who appears in Ace Attorney Investigations claiming to be the "Great Thief Yatagarasu". After meeting Edgeworth she joins him on his cases as his self-appointed assistant. She has a simulator called Little Thief, which assists Edgeworth during his investigations into a smuggling ring.
Kay features in the following cases: