Unknown webpage appears in 'history' for back button in IE:

Whilst browsing the Paradox Interactive forums this afternoon, I noticed something rather troubling.

 

Whilst looking at various threads here: http://forum.paradoxplaza.com/forum/forumdisplay.php?551-Crusader-Kings-II&s=2ee2dde83a9ec7fa2f7a13d380af60da

 

I went to click back, but in the list of sites between the thread I had been reading, and the Crusader Kings II forum, was another entry for something I've never heard of labelled : " Webcambait | Free pictures".

 

Now this site does not appear in the browser history window at all, nor in the drop down, address bar history. After doing some cautious google searches it appears 'webcambait' is most likely a pornography site of somekind judging from the google summary.

 

Essentially I am wondering why this appeared in the back button history when I never went to such a site and whether I should be concerned?

 

Thank you.