Back to base. Abbrevated to b2b.
If you're done doing whatever you were doing (a quest in an RPG, shopping at the grocer, finished work for the day, etc etc) and you're about to head home.
Guy 1: We finally killed all the murlocs we needed to, yay!
Guy 2: b2b
Guy 1: So, did we get everything on the list or do we need more cheese for the nachos?
Guy 2: Nah we're fine, lets head back to base