Rap music is an oxymoron, because rap is not musical. Rap is on one single pitch throughout the entire song. Some people like to pretend that rap music is musical, but people really laugh when others say that.
Billy: What are you listening to?
Bob: Nigga, Ima listenin' to rap music!
Billy: You mean rap. Not rap music.
Bob: Fo' shizzle! Ima gonna go rape my ho now!
Billy: You do that...