Azadi Emissary to the Northlands and governess of the associated provinces, she is stationed in the great Azadi Tower in Marcuria. Indeed, she has been tasked by both the Prophet and the Six to have the Tower finished in time for inauguration by the Azadi empresses. The Prophet apparently sees it necessary to threaten the Emissary, and she appears to fear him. After their meeting, she decides to work late into the night, asking her hand-maid, Alisa, to bring dinner to her office.
When April takes a look at the Azadi Tower for a night, she finds Sahya in her office, talking to the Prophet about the upcoming arrival of the apostle Kian Alvane in Marcuria, and shows concern about the motives of the Six for sending him. The Prophet advises her to let someone watch over Kian's steps in secret. She accepts this advice, but stays worried even after the Prophet left - so she orders her hand-maid Alisa to bring her dinner to the office, since she has to work for the rest of the night.
Some time later she welcomes Kian Alvane cordially and offers him help in his mission to kill "the Scorpion" . But since she's still suspicious of intervention from the empire's capital she asks Commander Vamon - seemingly her right-hand man, and even more unsympathetic to Alvane - to spy on him. This suspicion, coupled with Vamon's frequently-voiced irritation at Alvane's obedience to the Six, already indicates that the Emissary has her own agenda divorced from that of her empresses.
In Chapter Two: Awakenings, she is seen talking to Commander Vamon about Kian, the riot and the upcoming arrival of The First of The Six. During the unfolding events, she continues to discuss every new step with Vamon, which reveals that she has an strictly forbidden romantic affair with the commander. Their plan still seems to connect with the impending opening ceremony for the Azadi tower, and she shows ambitions to seize the sole power and rule the empire, with Vamon as her trusted confidant. Her obstacles include Kian, Hami and Mother Utana.
The "Art of Dreamfall" book that came with the Limited Edition names her "Sister Sayha". This is most likely a misprint in the book, as April mentions her name if the player uses the "Look" action on her before eavesdropping.