Zack was good friends with Pat back when they worked together, until he transferred to another branch. Back when Pat knew him, he was married to a woman named Kristy. Pat had met up with him again, a few years in the future and at this time, Zack had come out as a homosexual and gotten a divorce with Kristy. When he and Pat had a conversation about the events, there was an error in communication that led Zack to believe that he was also a homosexual. He invited Kenny and Pat both to play a game of gay dodgeball with them. When he realized that Pat wasn't actually gay, he shunned him out of their group of friends.