This answer: How do I delete a book off of my Kindle account? - shows that you can delete a book from your account/library on Amazon's web page.
What effect does this have on your Kindle readers?
Does it delete the book from the book list on Kindle devices?
Does it delete the book from the book files stored on Kindle devices (independently of #1)?
Do #1/#2 affect Kindle applications on various non-Kindle-device platforms as well?
DRM
protected. if note it will just be removed from thecloud
(librery). i don't know about 3.