Bohemian Rhapsody is a song by Queen. It is neither Bohemian nor a rap.
Because of the odd title, it is very clear that Frodo Mercury jumped in his time machine and went into the near future after running out of song ideas after the highly successful We Are the Champignons. There, he encountered the internet and Illogicopedia, the forerunner of Wackypedia. As he had only a limited amount of time, he copied off several articles before he had to return to 1975.
As the deadline for the new album approached, he stitched together parts of several nonsense articles although he rejected "Eeble sonk" out of hand. This gibberish was matched to musical fragments that Mercury had floating around for some time. The rest is history.