I learned that you can block offending followers from receiving your blog posts on their dashboard via Google Friend Connect. Unfortunately, you can't completely block a person from viewing your blog. They can still visit by entering in your url (web address) directly or they can subscribe through another reader.
How to block a Google Friend Connect follower
1. Log into your blog and go to your dashboard.
2. Click on #Followers beside the title of your blog.
3. Find and click on the offensive follower's photo.
4. Click on 'Block this user'.
5. Click on 'Block'.
Bye bye offending follower! :)
I created another blogger account to show you how to do this. Just in case you were wondering, the coffee photo is mine.
My advice to you: Take a look at your followers list every now and then so that you will be aware of what your readers are seeing when they visit your blog. I hope you don't ever have this problem, but if you do, hopefully you'll catch it earlier than I did!
Image Protection: Resize Your Photos!
Image Protection: Watermarks