Background
Zivjas was born into a fairly privileged life. Due to his father's connections he was able to grow up slightly sheltered yet more than comfortable life. Food, education, self-defense training, all valuable resources he had to start out with as a young Twi'lek. Things started to change however when his mother died. After turning to substance abuse to dull the pain, Zivjas' father's debts to the local hutt grew more and more difficult to afford both his lifestyle and vices. As life grew less and less glamorous and his father's addiction became more and more unmanageable, Zivjas was taken as collateral.
Thinking about the big picture, this Hutt figured he could train this new slave for entertainment, but when Zivjas was able to catch a guard by surprise with a wrist twist during his first attempt to escape, the Hutt decided to further test this boy and see if he would make for a decent assassin. He passed the Hutt's tests, and after his training, he would receive a series of progressively hard tasks to accomplish in between bounties that the Hutt would take a cut out of. "Kill this old politician, his time is soon anyways." "Kill this man, he's a murderer." "Kill this woman, she wronged many, including your master." He gradually seemed to take this level of indoctrination well given how gradually he was conditioned into it. However, after his latest mission turned out to not be killing a runaway slave, but rather a runaway parent, his baser instincts took hold, and he helped them hide before running away himself on the nearest transport.
With him being marked as a traitor from the one ally that gave him protection, he has nowhere to turn, other than to the closest bounty he can get to, armed with just a modified Slugthrower rifle and his skills which, due to his lack of sleep and paranoia, seem to be growing rustier and rustier. All for the slight chance that he could have his freedom and make his own choices...was it worth it?
Motivation
Ambition - Power
Nexxel desires that which was taken away from him: the power of his own voice. He wants to be able to hold onto what little goes against his conditioning as much as possible, hoping he will better understand himself.