Welcome to WebmasterWorld Guest from 220.127.116.11
[edited by: phranque at 10:45 pm (utc) on Sep 20, 2013]
[edit reason] exemplified domain [/edit]
you could test it by navigating to the IP address <http://18.104.22.168/> and finding and clicking the link to your domain.
I can't find the link they are using that comes back as the IP address.
img requests send referrer headers in all modern browsers I've looked into
looks like a direct request from their phpbbs script.