Tsavani works as a cook in the kitchen of the Thalmor Embassy.
Not unlike her kind, she is very familiar with Moon Sugar and appears to have an addiction. She smuggles it into her working and living place inside the Thalmor Embassy despite it being forbidden.
When the Dragonborn follow Malborn through the kitchen after escaping the party unseen they get stopped by Tsavani who immediately confronts them about how forbidden it is for guests to be in the kitchen. Malborn blackmails her using her Moon Sugar addiction and she let them both through.