Early in her life, she was sold into slavery to Zane Rythos, a ruthless human slave master, who was working for the Galactic Empire and kept Sinya as a personal servant and entertainer. As a teenager, Sinya attempted to escape, but Zane caught her and—displaying his legendary ruthlessness—cut off her right head-tail, which she eventually replaced with a prosthetic. However, Sinya escaped on her second attempt on the "Smuggler's Moon" Nar Shaddaa, where she started working as a criminal and mercenary, hoping to exact her revenge on Zane and the Empire that had once enslaved her.

Seeking out the rebellion, Sinya eventually was recruited after being observed and evaluated. Immediately she impressed her peers with her unprecedented speed at locating structural weaknesses in everything from buildings to vehicles, ensuring that she always planted her explosives where they would do the most damage. She now works as a covert operative specializing in disrupting and destroying technical and mechanical assets in the name of the rebellion.

Freedom: It has become too much the norm to enslave the Twi'lek people and she sees all Imperial rule as a form of slavery over the entire galaxy, Sinya is driven to bring freedom to all. She serves in the Alliance for the sake of liberty, which means she will be watching carefully for any signs that the Rebellion might replace on form of tyranny with another.

Vengeance: The Empire has committed acts that are unforgivable. Every dead stormtrooper, every destroyed Imperial asset is another notch on her gun, making her endless need to make them all pay. This tends to lead her to dangerous, even suicidal actions, especially if she doesn't find other feelings with which to temper it.

Sabotage

Tanned color skin, Green Eyes

Right lekku (head tail) is cybernetic. It is designed to function as her original lekku in the sense that she can move it and communicate with it as any other Twi'lek.