Blanks are human beings who have been captured by the Migou and brainwashed to be their unwilling slaves. Blanks are reprogrammed in such a way that they can still pretend to be the people they used to be, but that facade masks a robot that does anything the Migou want it to do. Blanks are used as cannon fodder on the frontlines and as spies, saboteurs and scouts within NEG territory. Tests devised by the NEG to detect Blanks have been unreliable and so they still pose a mortal danger to humans.
There are no Nazzadi blanks as the Migou kill any human-allied Nazzadi on sight, for reasons unknown.