Being the female leader of hell, Lucifer appears as a seemingly calm and collected person with a smooth arrogance on her face.
Despite her calm and collected behavior, it is shown that Lucifer is sometimes incompetent and unlucky when it comes to managing hell and its demons, even becoming embarrassed after seeing other demons didn't listen to her orders due to the fact that the demons prefer to follow her out of free will rather than respecting her. 
6'2", 700 pounds 