Gar Osen was a Bajoran male and member of the clergy.
In 2318, Gar was a prylar who attended Kai Meressa when the first Cardassians arrived on Bajor. When Meressa took members of the Oralian Way to see the Orb of Truth Gar questioned why she would do such a thing and was envious of the Cardassians, but Meressa explained her vision of the future to him and he was able to better understand.
By 2323, Gar had risen to the rank of ranjen because of his work with the Oralians. He was aboard Cemba Station when it bombed and was only saved because of Darrah Mace and Bennek. Shortly thereafter, Pasir Letin, an agent of the Obsidian Order posing as an Oralian cleric, abducted Gar and killed him. Letin then stole Gar's identity and posed as him for several more years. (ST - Terok Nor novel: Day of the Vipers)