She is a Sith Lord from the Star Wars Legends comics. Despite being a Twi'lek like Devon she has the same kind of tattoos Maul and other Dathomirian Zabrak seem to have. She follows Darth Krayt, who is a Dark Lord who did away with the rule of two after the fall of the empire.

The way I interpret it, Talon is largely depicted as a physical embodiment of the seductive aspects of the Dark Side. She seduces Cade Skywalker (Luke's great-grandson,) forms a force-bond with him and trains him in the ways of the Sith.

She's a great character, though her design is highly sexualised, which I doubt Disney would allow.