Answer:
I fly through the air on small feathered wings, seeking out life and destroying all things.
I heard of a wonder, of words moth-eaten. That is a strange thing, I thought, weird. That a man's song be swallowed by a worm. His blinded sentences, his bedside stand-by rustled in the night - and the robber-guest. Not one wit the wiser. For the words he had mumbled.
A skin have I, more eyes than one. I can be very nice when I am done.
I have one, you have one. If you remove the first letter, a bit remains. If you remove the second, bit still remains. If you remove the third, it still remains.
It cannot be seen, it weighs nothing, but when put into a barrel, it makes it lighter.
You use it between your head and your toes, the more it works the thinner it grows.