She was originally a member of the Kirin Tor of Dalaran, where her duties were to watch over the magical barriers protecting Atiesh, the legendary greatstaff of the final Guardian, Medivh. When the demon Archimonde destroyed Dalaran, the barriers were broken and Atiesh was shattered into many pieces. Dosantos left the Kirin Tor and began a search for the greatstaff which continues today. She first joined the Argent Dawn in order to help prevent Kel'Thuzad from gaining control of Atiesh, and has since been enrolled in the Brotherhood of the Light in order to pursue this goal more aggressively.
As a Watcher of Atiesh, she had access to many of Medivh's personal writings. In them, she discovered the secret to creating the Frostfire Regalia armor set for mages.