Whenever I'm in the bathroom, the door is closed, locked, and the fan is on, even if I'm doing something not-really-bathroom related like clipping my fingernails or brushing my teeth. It's just another one of my nervous habits, like checking a door a bunch of times when I leave the house just to make sure it's fully closed and/or locked even when I know it is... >_>;
And this is even if I'm home alone. 
