Doja used prosthetics to make her ensemble even more catlike, while Lil Nas incorporated whiskers and claws into his look.
The two stars have been rumored to be dating since February.
Her black-and-white gown was designed by Thom Browne.
"I'm representing the House of Chanel and Karl at the same time," Cardi said of her outfits.
The custom Jacquemus tweed suit was paired with a floral cape.
The look matched perfectly with this year's theme, Karl Lagerfeld: A Line of Beauty.
The actor came dressed as Karl Lagerfeld's cat, Choupette.
She paired the look with her hair in a long black braid.
The pop star left little to the imagination in his shiny ensemble, which consisted of metallic body paint, intricate jewels & a silver thong.
Doja channeled Choupette with a prosthetic nose and a cat ear headpiece.
