Sae originated from the planet Rei'izu and identified as female. During her youth, the Sith invaded her homeworld, and she was forced into service as a soldier for the Sith rebellion. She belonged to a squad of ten forced recruits which also contained Ekiya, Kabeji, Haba, Shogo, and Unsuke. Just one week following their departure from their home, the Dark Lord of the Sith, who would eventually gain the moniker the Ronin, turned against his Sith allies. The rebellion's downfall resulted in Rei'izu's inexplicable disappearance, leaving only a void of space in its place. The Sith officer in charge of Sae and her unit commanded them to mount a final defense against the Jedi and the Empire. However, they instead plotted to kill their commanding officer to gain their freedom. They succeeded, though only six members of the group lived through the revolt.
Subsequently, she and Haba developed a romantic relationship, and together, they were instrumental in establishing an autonomous communication network.