Answer:
What is often returned, but never borrowed/
What's as small as a mouse but guards a house like a lion?
The itsy bitsy teeny weeny yellow polka dot variety is quite popular.
I went to the woods and got it, when i got it didn’t want it, looked for it, couldn’t find it so I took it home.
They try to beat me, they try in vain. And when I win, I end the pain.
I’m grown from darkness but shine with a pale light. Very round I am and always a lady's delight.