Gelda Nebilim was born in N.D. 1966. She once led part of the Oracle Knights in the Order of Lorelei, serving as Locrian Colonel during her tenure. Under orders from Fon Master Evenos, she runs several special investigations into relics known as the Catalyst Weapons, six weapons that shared the power of Rem and Shadow, the aggregate sentiences of Light and Darkness. At one point during these investigations, Nebilim fails a planetary arte experiment administered at Mt. Roneal, resulting in the death of many Oracle Knights in N.D. 1991. After the accident, she leaves the Oracle Knights and opens a private school in the Keterburg. Unlike any teacher before her, Professor Nebilim shares an important bond with her students, treating them as children she never had. Upon the arrival of a young Jade, Nebilim senses the boy's twisted mind, lacking no ability to distinguish the guilt or the pleasure in taking a life for achieving his ends. Realizing this, she seeks to change his heart, leading him to develop his fomicry methods to form a better cause.