Answer:
I am mother and father, but never birth or nurse. I'm rarely still, but I never wander.
A little pool with two layers of wall around it. One white and soft and the other dark and hard. Amidst a light brown grassy lawn with an outline of a green grass.
Slayer of regrets, old and new, sought by many, found by few.
Its title means book.
A horrid monster hides from the day, with many legs and many eyes. With silver chains it catches prey. And eats it all before it dies. Yet in every cottage does it stay. And every castle beneath the sky.
What covers its face with its hands, speaks no language, yet most known what it's saying?