Answer
When you block someone, they will no longer be able to send you Mails and eCards. If they try to send you a Message or eCard they will get a sign that they have been blocked – so they will know you don’t appreciate what they have previously sent.
The Mail and eCards they previously sent you will still remain, but you can delete them if you want.
They can still view your profile and send you a "Like". But each member can only send ONE Like, so they can only do this once.