HELP ID worm with pics! (3)

[bonzanin]

Hello,

I have some of this worms and I want to know if they are OK...
Questions:
1- What is the following worm?
2- Is it a harm? Do it eat/kill/bothers any corals at all?
3- If so, how do I remove it? Is there any fish that eats it?

Thanks!

 

[SushiGirl]

Harmless feather duster.

 

[bonzanin]

Thanks!