Answer:
A home of wood in a wooded place, but built not by hand. High above the earthen ground, it holds its pale blue gems. What is it?
I have legs but walk not, a strong back but work not. Two good arms but reach not. A seat but sit and tarry not.
My life can be measured in hours, I serve by being devoured. Thin, I am quick. Fat, I am slow. Wind is my foe.
My first master has four legs, my second master has two. My first I serve in life, my second I serve in death. Tough I am, yet soft beside. Against ladies cheeks I often reside.
I know a word of letters three. Add two, and fewer there will be!
Special abilities and brightly colored underwear are all you need to be one of these.