She was a girl to be sacrificed to Nereza by Rayeld. However, he had a change of heart and spared her, killing his father, High Cleric, instead. The two then attempted to destroy Nereza, and although her physical body was killed, the demon managed to take Sara's life in her last moments..
Her corpse can be found atop the Ancient Tower, in form of a bloodied, charred skeleton. There is no interaction with it.