Graveyard shift. e.g. I'm working the graveyard shift tonight, so I will sleep all day.
Working at night
Scaredy cat. e.g. C'mon, try bungee jumping! Don't be such a scaredy cat!
Don't be scared
Ghost town. e.g. I went for a walk at 5am. I didn't see anyone around, it was like a ghost town.
a place where there is few or no people
Dig your own grave. e.g. A: I'm going to skip English class. B: Okay, but you are digging your own grave for the test.
You are doing something which cause problems for yourself later.
drop-dead gorgeous. e.g. She looked drop-dead gorgeous in that dress.
Very beautiful
Night Owl e.g. I don't like waking up early, I'm more of a night owl.
Someone who likes being awake at night.
Skeleton in the closet.
Something you want to keep secret; possibly embarrassing