The singer and TV personality made for the perfect partners-in-crime at the lavish soiree.
Mariah Carey doesn't just love butterflies, she is one -- a social butterfly, that is.
The diva attended the always lavish and incredible Elton John AIDS Foundation Oscar Viewing Party in West Hollywood, California, on Sunday, where she hung out with many an A-lister.
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Mariah made sure to get a snap with the man of the hour himself, who looked dashing in a sparkly navy blue suit and matching sunglasses.
Elton smartly pointed out that Mariah was rocking a serious amount of bling to the shindig, which happened to include her massive 35-carat engagement ring. "Mariah looking glam-fabulous. She's wearing more carats than I am!" he wrote on Instagram.
The 45-year-old singer, who wore a one-shouldered black dress with a peek-a-boo pink panel in the leg slit, also sat with a fierce and fabulous-looking Kelly Osbourne.
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Kelly's purple bangs and that skull cane? Everything, darling, just like the pair's selfie skills:
Seriously, they love each other, and it's the best.
Kelly was just as big a reveler as Mariah, goofing around as she tablehopped.
"I think Kelly Osbourne inherited her sense of humour from her mother. Sheryl Crow and I are unimpressed," Elton joked.
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Many more celebrities turned out for Elton's annual soiree, including tablemates Lana Del Rey and Hilary Swank. Both glistened, with Lana channeling old Hollywood glam in a pale Bulgari gown and Hilary rocking a disco ball-inspired top and black skirt.
Steven Tyler also joined the fete, posing for a photo with Elton and the British singer's husband, David Furnish.
And just before the Oscars kicked off, Elton excitedly took a pic with Boy George and Caitlyn Jenner…
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… who Kelly bonded with as well.
Really, Elton's table card said it all: This was one "wonderful crazy night."
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Check out even more pics from the fabulous bash below:
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