The star, 41, strutted into the celebration in Beverly Hills, California, on Monday night wearing a stylish superhero ensemble featuring a skin-tight, black leather outfit and extra-large black sunglasses.
The 41-year-old entrepreneur also showed off her toned abs in a black leather crop top with a plunging neckline which she paired perfectly with the high-waisted pantashoes — a hybrid clothing item that combines skin-tight leggings with built-in stilettos.
The mother-of-four accessorized the look with the luxury brand’s mini, metallic silver croc-embossed handbag, which features a rhinestone-covered B-shaped clasp.
Khloé also sported a skin-tight look for her birthday celebration, however, the birthday girl’s version was in stark contrast to Kim’s all-black outfit. The Good American founder wore a hot pink latex dress for her special day.
With matching vibrant pink heels, a blonde, straight lob and gorgeous glam makeup, Khloé looked like a stylish real-life Barbie.
Before the sisters got all dressed up for the big night, Kim gave Khloé some birthday love on Instagram, calling her “my number 1 ride or die” in a carousel post full of candid photos of the two enjoying slices of pizza.
“I feel so blessed to be your sister and call you my best friend! No one in this planet deserves the happiness and blessings that are coming your way,” wrote Kim. “Every single person that is blessed to be close to you is a better person because of you. I am so proud of your heart and how genuine you are.”
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The SKIMS founder continued, “You are always true to yourself and always want what’s best for others! Your heart is so pure that I can feel all of the best energy coming your way. I love you so much and couldn’t get through this life without you ✨♾.”