To bail on ones bro(s).
Chris: Hey dude, you still want to go grab some grub?
Nate: Sorry man, change of plans. I'm just going to jack off to some gay porn.
Chris:...You fucking bro bailer.
Scott: Ian, didn't Nate say he was coming to our kegger tonight?
Ian: No, he decided to stay in to watch the Gossip girls marathon with his gf.
Scott: Wow, what a douche.
Cory: He's like the unholy king of bro bailing.