Answer:
They're up near the sky, on something very tall. Sometimes they die, only then do they fall.
A doctor might remove one from the neck of a Dracula victim.
The sharp slim blade, that cuts the wind.
I'm not man's best friend, I'm their enemy, I can mark your end, yet you do not see me, I am very small, but very tough, If you have me, then you have it rough.
My first is in wield, sever bones and marrow. My second is in blade, forged in cold steel. My third is in arbalest, and also in arrows. My fourth is in power, plunged through a shield. My fifth is in honor, and also in vows My last will put an end to it all.
I never sleep yet sometimes I weep. I can get angry or just be happy. Wherever you go, I will follow. No matter what you do, I will be there. I cannot die. What am I?