Answer:
Useful tool for who in darkness dwell. Within you, corrupting like a deadly spell.
Take off my skin, I won't cry, but you will.
What can be forever wound up but never annoyed?
It's usually found dried, but often kept slicker. Above another need, it's said to be thicker. What is it?
Hold these between your knees if you want to set a Cuban beat.
The warmer I am the fresher I am.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?