Answer:
This is needed both for courage and hardcover books.
It is by nature, soft as silk; A puffy cloud, white as milk; Snow tops this tropical crop; The dirtiest part of a mop
Turns us on our backs, and open up our stomachs. You will be the wisest of men though at start a lummox.
I am the yellow hem of the sea's blue skirt.
What kind of pet always stays on the floor?
If it’s information you seek, come and see me. If it’s pairs of letters you need, I have consecutively three. What am I?