Ninja from Die Antwoord performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012. (Photo by Sitthixay Ditthavong/Invision/AP)

Associated Press
Ninja from Die Antwoord performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012. (Photo by Sitthixay Ditthavong/Invision/AP)
Ninja from Die Antwoord performs at Lollapalooza in Chicago's Grant Park on Friday, Aug. 3, 2012. (Photo by Sitthixay Ditthavong/Invision/AP)