Answer:
Hard to catch, easy to hold. Can't be seen, unless it's cold
In this place, people lie, people cry, and people ask why. In this place, people sleep, people weep, and people's solitude, they keep. What is it?
Useful tool for who in darkness dwell. Within you, corrupting like a deadly spell.
They're up near the sky, on something very tall. Sometimes they die, only then do they fall.
I grow where no flower grows, where no light touches the walls, up or down, that I don't care, was here before people were.
I fly to any foreign parts assisted by my spreading wings. My body holds an hundred hearts Nay I will tell you stranger things when I am not in haste I ride and then I mend my pace anon.