Answer:
My first is second in line; I send shivers up your spine; not quite shining bright I glitter in the light.
I am lighter than air, but a hundred people cannot lift me. Careful, I am fragile. What am I?
I am the key that is the hardest to turn
I run up and down the stairs without moving. What am I?
I am round. I have only one line. Circle is not my name indeed. What am I?
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?