Background
Tira was orphaned on Coruscant before she could remember anything and grew up alone in the Lower Levels. Shortly before the Battle of Yavin, she helped out a man with various tasks. He turned out to be a spy for the Rebel Alliance. Seizing the opportunity to escape her circumstances, Tira joined as a spy reporting directly to her mentor. She handled more unscrupulous tasks for the Alliance. She was on a mission on Coruscant during the Battle of Endor, while her mentor died during the battle. As the New Republic tries to move away from some of the unsavory tactics used during the Galactic Civil War, Tira was reassigned to the Outer Rim.
Motivation
Tira is trying to find out where she belongs in the new galactic order, especially without her mentor. She has always worked alone, both growing up and in the Rebel Alliance. Now she is having to learn to work with a team. She can be impatient when waiting for others to make a decision.
Her primary motivation in life is survival through whatever methods she deems necessary. As she has served in the Rebel Alliance, this has come to include ensuring the survival of those she considers important to her.