A black friend of a white, asian, or hispanic guy. Could be the token black guy that people are seeking out to complete their social circle. Lends credibility to someone trying not to appear racist.
-I can't make it, I'm going bowling with my Afbro.
-You have an Afbro? Since when?
-Since I started keeping it real. Your crew is whiter than Crisco.
-Damn, I just got served.