Raireza is a supporting character in the Tenchi Muyo! Ryo-Ohki continuity, appearing in the GXP novelizations.
Background
Raireza's background is unknown, not even having a revealed surname.
Raireza is one of Airi Masaki's leading researchers in her many workshops and is an accomplished philosopher in her own right. She is the head researcher and continuing developer of Galaxy Police's Guardian Systems. When Seina arrives at the academy, she works in a key support position for Airi and when checking the security on the NB Airi gave him, she is the one to discover that Kirche had made it her home.
When Miki Steinbeck is apparently killed and fails to transfer her astral to NB, she and Hakuryo Masaki serve as contacts with Hiroshi Manada to investigate the circumstances behind the incident and find out whether or not she survived.
While working with Hiroshi, she comes to have feelings for him. When she brings him to her home for dinner and drinks in an effort to get him to take a break from stressing about his daughter, she asks about his life story and triggers the memory that allows him to figure out the encryption code for the message MIki left in NB in her failed transfer.
They start dating soon after.
Possibly due to wealth gained from the surely lucrative patents she would have for the Guardian Systems, Raireza is conspicuously wealthy. When she brings Hiroshi to her home, she first takes him shopping for extremely expensive alcohol and when they arrive at her home he remarks at how impressive her penthouse apartment is. She then informs him that the entire building is hers, the other floors are storage and research laboratories, and that she owns the entire garage of cars in the underground parking lot. She even offers to give Hiroshi one of the cars, his pick. Hiroshi, although on much firmer financial ground while working for Airi, can't even contemplate the expense the insurance would cost him on one of them.
She is apparently one of Amane Kaunaq's closest friends. Her first brief appearance in the novels is as a visitor when Amane is moving into her new home. Also, when Amane is contemplating whether or not to marry Seina, it is Raireza that she calls to talk about it (Airi fills the advice role for all the girls in the anime).