Answer: Backstage
Step-by-step explanation:
Backstage is a behavior, which can be related with the actions of the performer that occurs at the back but audience cannot visualized and realized it.
When Sue goes to work, she has to present herself in front of the audience, so she needs to put up a makeup. But at home she knows that no one would be concerned about her appearance thus her home is like a backstage of her life. Thus she does not care about her looks at home.