Answer:
According to the music industry, you can count on a midnight train and the devil to turn up here.
Voiceless it cries, wingless flutters, toothless bites, mouthless mutters.
Die without me, never thank me. Walk right through me, never feel me. Always watching, never speaking. Always lurking, never seen.
Sometimes black, sometimes white, I have veins but no blood
I go around in circles, but always straight ahead. Never complain, no matter where I am led.
You use it between your head and your toes, the more it works the thinner it grows.