Royce Da 5'9 is an American rapper. He has released mixtapes and albums including Book of Ryan, The Allegory, and The Bar Exam 4. He has worked with Eminem and Dr. Dre, formed the groups PRhyme and Slaughterhouse, and his most popular songs include Boblo Boat, Caterpillar, and Detroit Vs. Everybody which features Eminem and Big Sean.