Fusker site does not store your data in it's own server. It will be requested from your server each time the user visit the image. So if you want to completely block particular site to deny your Images to be displayed then we strongly suggest to
.htaccess blocking rules or use
Enable HotLink Protection.
.HTACCESS BLOCKING RULES:
RewriteEngine On
RewriteCond %{HTTP_REFERER} ^http://(.+\.)?blockedsitename\.com/ [NC]
RewriteRule .*\.(jpe?g|gif|bmp|png)$ - [F]
ENABLE HOTLINK PROTECTION (cPanel Example):
Login to your cPanel and select
HotLink Protection.

And follow the details