What's the difference between blocking and hiding another user?
When you block a user, they disappear from your lists and messages, but more importantly, you disappear from all of their lists and messages, too.
When you choose to “Hide” a user (for example, if there is someone in your Admirers lists that you are not interested in, and no longer wish to see them there), they simply disappear from that list on your end. They would still show up in your search results, you would still show up in theirs, and both of you would be able to view each other’s messages in the messaging center. You just would not see them included in the specific list you hid them from.