Brock was a member of the United States Military. The United States wasn't suited for him after he retired from the Army. Therefore he moved to Chernarus because of all the good things he heard and the school system hoping to find a place to settle down and have kids. He found a place in Balota to settle down but whilst moving in his wife was infected and Brock tied her to the bed and left. He is mentally broken and has no remorse after what these things are done to his wife. He's not sure whether or not everyone else is infected but he knows that he will kill to survive even if that involves eating people wich he enjoys.