Also a form of male bonding to such a point where they start to seem like a couple.
This bond is normally only shared between two males that have a deeper understanding of each other, in a way no woman could ever realize.
Guy 1: Dude, want to come over and watch the football game and bro out!?
Guy 2: Yeah bro, I need to relax. I'm all worn out because I've been putting up posters of attractive women to mask my obvious homosexuality.