You are a ghost, living among humans still on earth. No one can see you, so you could go anywhere you wanted and do what you wanted. You were living in some old house, until a man moved in. At his first day in this house, he was on a couch reading when you were casually just walking around and to the kitchen. But suddenly, the man puts book away

"Um...excuse me, but how did you get there?"

He asks you as he stands up, staring at you suspiciouly

"I thought i locked all doors. Who are you?"