Stupid Roommates

According to the landlord, there should be four people living here.  Then why do I count five rooms being used?  That's right, one of them hasn't found a new place to live.  So he squats.  I love the morals of these people.  He doesn't ask us if we mind, he just stays.  Granted, it's not a major inconvience, but still, wtf?  Does he not have friends he can crash with?  He says he's moving out, and I believe him, but still, it would have been nice if he asked, don't you think?