Cus was a Jedi Knight who, helped establish a network of various rebel cells against the Galactic Empire. Born on Coruscant, Cus received Jedi training from her older brother Mojito. However, this would not last, as Mojito, who grieved his Master's death and loss of faith, left the Jedi Order, Cus would be later trained by her sister Jedi Master Vados. Following the outbreak of the Clone Wars, Jedi Grand Master Shin I assigned the young Cus alongside Padawan Cabba, whom she joined at the Battle of Christophsis.

Cus gained much experience on and beyond the war front, leading a group of Jedi younglings to revolt against their Trandoshan captors, helping rescue a colony of Togruta from enslavement by the Zygerrian Slave Empire, and serving as an advisor to the Onderon rebels—with her close friend, Lilibeu, among them—as they liberated their world from the Confederacy.

Towards the end of the war, Cus, along with Cabba, was made a Jedi Knight. This blissful moment proved to be short-lived, however, as a few days later Order 66 was used by Chancellor Kann to destroy the Jedi. Cus went with Cabba to confront Korn, now named Darth Vader, on the planet of Mustafar until Hit arrived. After Hit's duel with the Sith Lord, Vados gave birth, knowing that the boy would in danger if he stayed with his parents, Hit entrusted Cabba to take care of his newborn son, Mira, who he took to live with him and Cus on the planet Tatooine. During their exile on the planet, Cabba and Cus trained the young Mira under the ways of the Force.

Around 2 BBY, Cus, along with Cabba and Mira joined the Rebel alliance after feeling the destruction of Alderaan through the Force. After the Battle of Yavin, Cus helped Vados to guide to Rebel Alliance to fight the Empire.

In Endor's aftermath, the Rebellion formed the New Republic. Vados was elected as the first chancellor of the New Republic Senate with Cus being the Senator of Naboo, however, Cus would eventually left the Republic to aid the next generation of Jedi alongside Cabba who became the Grandmaster of the New Jedi Order.