Ghost performs in an eccentric style with five of the six members wearing robes, while the vocalist wears a cassock and has a skull painted on his face. The identity of the members is highly secretive. The members of the band are called 'Nameless Ghouls', while the vocalist is known as 'Papa Emeritus'. Papa Emeritus changes uniforms again every so often. After the first drastic costume change, the singer renamed himself Papa Emeritus II to suggest a different singer. For the 2015 album 'Meliora', he underwent a new transformation and used the name Papa Emeritus III.

On 1 October 2017, during the final performance of the tour in Gothenburg, Papa Emeritus III was suddenly forcibly removed from the stage by two men. At this, a new character appeared on stage: Papa Nihil. He declared (in Latin) that the party was over and a new era was dawning: the Middle Ages.

On 6 April 2018, it was announced on YouTube that, to Papa Nihil's displeasure, the bloodline was being severed, as there were no further descendants, and Cardinal Copia would become Ghost's new frontman. Also, Papa Nihil's sons (which is believed to refer to Papa Emeritus I to III) would be given a new mission. When it was communicated by Sister Imperator to Papa I, II and III (who, incidentally, were collectively playing Uno) that they would be reinstated and go back on tour in full costume, they were killed by a Nameless Ghoul and then embalmed and put in flight cases so that they could be laid out at the VIP experience and selfies taken with them, among other things.

On 3 March 2020 during the final concert for the album 'Prequelle', Papa Nihil collapsed during his saxophone solo. Cardinal Copia was transformed by nuns into Papa Emeritus IV who became Ghost's new frontman.

On 11 October 2015, webzine Lords of Metal raised the suspicion that Papa Emeritus III might be Tobias Forge of Swedish band Magna Carta Cartel, which was later confirmed by the band itself.