Joey Bada$$ performs at the Hanger Lounge on March 14, 2013 during the SXSW Music Conference.
Shannon Stewart for Fuse

Joey Bada$$ and the Pro Era crew repped Brooklyn and the East Coast hard at this year's SXSW. But for one dude watching their rooftop set on Thursday night, the incessant East Coast rap pride proved too much to handle.

After Bada$$ got the whole crowd chanting the group's "Beast Coast!" rallying cry, one guy took it upon himself to defend the honor of West Coast rap by shouting—you guessed it—"West Coast!" over and over… and over.

Pro Era didn't seem to take notice, but one audience member made it his business to halt the "West Coast" chant immediately. Turning around with severity of Professor Snape tearing into Harry Potter, this unimpressed stranger rebuked the West Coast cheerleader with one syllable: "No."

It wasn't spoken as a counterpoint, it wasn't uttered as a command, but it was delivered with the quiet forcefulness of disappointed father. And it shut down the guy immediately.

Mr. West Coast offered a compromise by saying, "Well, they're both good," but it was met with another deadpan "no" that carried the severity of Grumpy Cat's face (who, coincidentally, was at SXSW this year). After his final defeat, the West Coast rap enthusiast shrunk backward into the crowd like an embarrassed Michael Cera.