I'm not really good at writing or at English, but I made a little backstory for him.
Prevador was a former Aeonyx (A very cool species created by @alieraah, she even made a site: http://aeonyx-empire.tumblr.com/, check it out)
Prevador had a lot of criticism on the way The Court (The government) ruled over the Aeonyx. Beside all his effort to change the society, it didn't work out. Most of the Aeonyx were making fun of him. This made him furious. He didn't feel at home by the Aeonyx anymore. Prevador eventually left and perished in exile. His choice to leave did change his physical look.
I'm going to make his previous appearance later.
Please correct my English if I'm wrong. Criticism is also welcome!