Freddie was ietwat boos.
The song was written by Freddie Mercury about the band's fall-out with their original manager and Trident Studios owner Norman Sheffield. Though the song makes no direct reference to him, Sheffield sued both the band and the record label for defamation. This resulted in an out-of-court settlement, thus revealing to the public his connection with the song. Mercury said that his lawyer had cautioned him against discussing the lyrics, but that it was written from a "very emotional" place for which he felt music was the best outlet.
Roger Taylor also noted that despite the success of "Killer Queen" and Sheer Heart Attack, the album preceding A Night at the Opera, the band was lacking money before the album was made. Freddie Mercury later recalled that he had tried to make the lyrics as "coarse as possible", and that the other band members were initially shocked at the harsh lyrics. However, the band agreed that the song should be performed as Mercury intended, and it was recorded as such.
During live performances Mercury would usually dedicate the song to "a real motherfucker of a gentleman." This line ("This is about a dirty, nasty old man, we call him motherfucker, you know what motherfucker means?") was shortened and censored on Live Killers.