Who is Omi Inamura from The Key to Midnight and what is their importance?

Omi Inamura is Mariko's uncle and a psychiatrist. Mariko tries for years to get Joanna to see her uncle, but when Alex comes along and tells both Mariko and Joanna who Alex believes Joanna to be, Joanna finally agrees to the psychiatrist. Inamura agrees to put Joanna under hypnosis in order to find out what happened to Lisa Chelgrin. Inamura manages to regress Joanna to the time when she was brainwashed and is even able to dismantle some of the posthypnotic suggestions she was given. However, Inamura is unable to return to Joanna her memories of Lisa Chelgrin. It seems that those memories have been thoroughly destroyed.