Billie opted for some drama on the blue carpet, donning a stunning Rick Owens black gown that featured a plunging neckline with a sheer cover-up.
Billie and Jesse twinned in black at the Vanity Fair party
The main attraction was definitely the sweeping tulle skirt that took up yards of space around the singer, even subtly hiding the black mini dress she wore underneath.
Musician boyfriend Jesse posed alongside her in a sleek black suit accessorized with a bright red scarf, white rose lapel, and blue suede shoes.
The 21-year-old Bad Guy singer did switch things up after walking the carpet, going for a more comfortable ensemble while at the party, keeping with the black to match her raven locks.
Inside the actual event, she wore a pantsuit with a chic velvet oversized blazer, twinning more with her boyfriend while she mingled with all the other stars who brought the glitz, which you can check out in the video below.
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While Billie and Jesse, 31, started dating earlier last year, they didn't go public with their relationship until they hit up another carpet together, the LACMA Art and Film Gala in November.
The duo attended in matching Gucci ensembles, with the former's featuring the logo emblazoned across an olive green nightgown while Jesse wore matching pajamas for his red carpet debut with his girlfriend.
The singer switched it up once she headed inside
The two wrapped up in a large blanket to pose on the carpet. Billie's brother Finneas was also in attendance, and they were seen posing alongside several other celebrities such as Elton John.
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