Headmaster Martine
He was the headmaster of Galbadia Garden. Martine is responsible for giving the order to Squall and the others to assassinate the sorceress. Martine said that Balamb and Galbadia Garden agreed to it, but he lied, it was really a last hope try to assassinate Edea. He retired to Fisherman's Horizon after the mission having quit his job as headmaster.
Raine Leonhart
Raine Leonhart is Laguna's love interest/wife. She is the mother of Squall Leonhart.
Xu
Xu is among the many students at Balamb Garden during the events of Final Fantasy VIII. Though only a minor character, she pops up quite often throughout the game. She has dark hair and is always seen wearing her SeeD uniform. Later in the game (if one continues the Triple Triad side-story against Balamb Garden's best CC players), it is revealed that Xu is also the famous CC's "Heart".
Nida
A student of Garden that appears to pass the SeeD field exam at the same time as Squall, Zell, and Selphie at the beginning of the first disc. Re-appears on the second disc to pilot Garden after it transforms back into the Mobile Centra Shelter