Nicki Minaj is known for her over-the-top stage persona, but her performance at Sunday's 54th Annual Grammy Awards took things to a whole new level.

Wearing an Oscar de la Renta dress, the 29-year-old shocked viewers when she performed her new song "Roman Holiday" for the very first time. Channeling her alter ego Roman Zolanski, Minaj's performance pushed religious boundaries.

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"I had this vision for Roman for him to be sort of exorcised," she explained on Ryan Seacrest's KIIS-FM radio show Monday. "People around him tell him he's not good enough because he's not normal and he's not blending in with the Average Joe."

The Grammy nominee's performance included a Catholic confessional, demonic possession, dancing monks and a levitation scene.

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"The people around him are afraid because they've never seen anything like him. He wanted to show that not only is he amazing . . . but he's never going to change. He's never going to be exorcised," Minaj said. "Even when they throw the holy water on him, he still rises above."

The rapper's performance angered the the right-wing Catholic League, who issued a press release condemning it Monday. "Whether Minaj is possessed is surely an open question," president Bill Donohue said, "but what is not in doubt is the irresponsibility of The Recording Academy. Never would they allow an artist to insult Judaism or Islam."

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"It's bad enough that Catholics have to fight for their rights vis-a-vis a hostile administration in Washington without also having to fend off attacks in the entertainment industry," Donohue seethed. "The net effect, however, will only embolden Catholics, as well as their friends in other faith communities."

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Minaj, meanwhile, stands behind her elaborate stage show. "It's the most comfortable I've ever been onstage in my entire life," she said.

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