Just as you need a wing man to help pick up chicks, sometimes it's necessary to bring a wang man to go the bathroom. Sometimes it's to give you moral support an other times it may be to give you someone to talk to while you're pinching one out. Most importantly, above all else it is not gay to be a wang man or have one.
1."Hey dude, do you think you could be my wang man? I gotta unload one"
2. "Hey bro, do you mind coming with me? This might take a while and I'm gonna need a wang man"