Dr. Naomi Hunter (ナオミ・ハンター博士 Naomi Hantā Hakase) is a geneticist by practice, and specializes in nanotechnology-based gene therapy.
In Metal Gear Solid, she is the chief of FOXHOUND's medical staff and part of the support crew assembled to assist Solid Snake, providing the player with information on the FOXHOUND members Snake faces. Being Gray Fox's adopted sister, she attempted to get revenge on Snake for attempting to kill her brother. When instructed to inject Snake with the FOXDIE virus, she secretly modifies it so that it will kill Snake at a random moment in addition to its original programming. As the game progresses, Naomi realizes that some of her original perceptions of him were wrong and is later remorseful for modifying the virus. Uncertain of when exactly the FOXDIE would kill Snake, Naomi tells him to live his life to the fullest in whatever time he had left. Afterwards, Nastasha Romanenko's account reveals that Naomi was briefly arrested following the Shadow Moses incident until her escape.
In Metal Gear Solid 4, Naomi is working with Liquid Ocelot in order to hijack the SOP battlefield control system, but joins Snake's group once again. She becomes romantically involved with Otacon and forms a friendship with Sunny. When they return to Shadow Moses, Naomi reveals that she has been diagnosed with terminal cancer that has been kept in check by nanomachines and, guilt-ridden over her past mistakes, commits suicide by disabling them.
Naomi Hunter is voiced by Hiromi Tsuru in Japanese and Jennifer Hale in English.