There are a lot of spooky things at night. The house can creak and groan when it settles, we can't see into the dark, and our imaginations can start running wild with wonderings about what is just outside of the light. It doesn't help when we actually experience things we can't explain or when other people tell us such things aren't possible. How can we be sure the things we "know" are really true?
There are two different worlds on Earth. There's the daytime animals and human activities, and when all of them go to bed, the others come creeping out. But humans still tend to circle the bonfire or eat at the brightly lit all-night restaurant, or work third shift under the factory's sodium lights. At heart, I think most of us are afraid of the dark.
The owl eyes are colored pencil on black construction paper. The bats are watercolor and pencil.