A sentry, with the bare minimum requirements to be called "Humanoid." Since it is a robot, But has acquired a look of a feminine body despite only having one arm to hold the Heavy Machine Gun. And only a slim metal pole as her waist. That is how expensive it is to make sentries. "Turret-Chan" was created. It's original purpose was to be a stationary, lifeless, automated killing turret. Killing anything that moves in its sight... now... it had become sentient from an unintended system bug...