There are several updates -- read through the whole thing for additions at the end!
Start at the Menu bar on upper left and go to "Friends" page. (See addition below for more information.)
Click on "Followers" to get all the people who follow you.
In the upper right corner of each listing is a square symbol made of two arrows.
When your cursor is within the listing/profile space, another symbol -- a circle -- will appear to the left of the arrow-square. If you move the cursor out of the listing/profile space, the circle disappears.
Click on the circle to block that follower. You'll get a message to confirm.
If you discover you've blocked someone you want to UNblock, go to the list of Blocked accounts (see first picture) and do the same thing to unblock them.
NOTE: Per Themis-Athena's Garden of Books
Note: If you block and then unblock someone, they will only be taken off your "blocked" list, they will *not* be re-added to your list of followers.
So on the one hand, that is a way to get rid of followers you just don't want, without actually feeling the need to block them. OTOH, if blocking them was an honest mistake and you don't mind to have them among your followers, you may want to PM them to let them know that they need to re-follow you.
I don't know why the block button only shows when you're in the space. It should just be there like the other symbol. But I don't know why BookLikes does a lot of things the way they do.
** The two buttons do not show up if you click on "Followers" from your blog page.
The profile/listings that come up when you click on "Followers" from a blog post have no buttons at all. You have to go through the main menu and "Friends" button.