The hit away is a piece of **** from Wal-Mart. It isn't possible to hit with good mechanics on it IMO. I think the good old fashioned tee and net works better.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .