Scene From The Movie: When MC Gusto dresses as Sissy
Real life examples: Hopsin, Lil Wayne's jeggings, Young Thug's skirts
We all have reasons for wearing the things we wear: for instance, I put on a coat when it gets cold. In CB4, in an elaborate and probably unnecessary twist, Albert dresses up in Sissy's skimpy pink lingerie in order to arrest Gusto for escaping from jail. (Why they couldn't have arrested Gusto without this adventure into cross-dressing, we'll never know.)
Anyway: that does little to explain why Young Thug wears skirts or Lil Wayne tights. Fashion is like an umbrella; it covers everything and everyone. It'd be nice if there were some higher purpose, like one of those rappers working with the FBI to bring down corruption on Wall Street.