Let me start off by saying my cat has always been the sweetest, most warm, and well natured cat I've known or owned. He's almost a year old, and he's always loved company and new people. Recently however, he's started to be very aggressive. Every time someone comes over he hisses, howls, and has gotten physical twice. His attitude does a complete 360. Let me note, the moment company leaves, he's fine. He's calm, cuddly, and sweet. Any idea on what could have happened developmentally or physically to my sweet kitten over the past two months to make him act so differently around strangers so suddenly.


He's strictly an inside cat.
He's never been physically harmed by a person, other animal, etc.
He started presenting these behaviors about two months ago.


We don't believe it to be territorial because he's even aggressive towards us.

He is territorial and probably not neutered, which would make him more so going into adulthood.