The 42-year-old looked phenomenal on Tuesday when she was photographed alongside her fiancé, Matthew Rutler, 37, exiting 'Jimmy Kimmel Live' in a pair of skintight, shiny black pants, and a plunging satin top that highlighted her tiny waist and curves.
Christina wore her shoulder-length, platinum blonde hair down with a subtle wave, and accessorized her décolletage with layered, silver necklaces.
She added matching, hooped earrings, a pair of black sunglasses, and killer heels to complete her look.
The 'Dirrty' singer's figure-hugging outfit was different from what she was pictured in when she arrived at the studios earlier in the evening.
Christina opted for an oversized, black leather jacket with matching heeled boots, which she teamed with a cropped, hooded sweatshirt, and a simply black top. Adding a pop of color, she wore a red mini skirt with beaming white teeth emblazoned across the front.
The mom-of-two has a penchant for daring, figure-hugging outfits and loves to showcase her curves after admitting she "hated being super skinny" during the early days of her career.
"Entering this business, I hated being super skinny. Once I turned 21, I started filling out a little bit, and I was loving my new curves. I appreciated having a booty," she previously told Health.
Christina saw her weight fluctuate following the birth of her son, Max, now 15, in 2008, and her divorce from music composer, Jordan Bratman, 46, in 2010. However, two years later she dropped 40lbs after turning to the 'Rainbow Diet'.
The singer appears to have relaxed her eating habits over the years and is more focused on consuming clean, whole foods and limiting sugar, revealing in 2020 that she has given up dieting.
"I'm not going on a diet, get over it," she told L'Officiel Italia. She added: "Each of us is an individual and people judge you based on your differences, on what makes you unique. You have to accept that beauty and to hell with everything else."
Christina's latest appearance comes after she announced she will be performing a series of "intimate" shows at the Voltaire Belle de Nuit at The Venetian Resort for her new Las Vegas residency starting New Year's Eve weekend.
Sharing a promotional image on Instagram, she penned: "Immerse yourself in the fusion of art and music. I'm bringing an intimate, seductive and sophisticated new show to Las Vegas. @voltairelv will allow me to be up-close-and-personal with YOU for a truly modern twist on the performance experience, TICKETS ON SALE FRIDAY!"
In a statement about the upcoming residency, the 'Hurt' singer gushed: "I look forward to bringing Las Vegas a new show that fuses music, sophistication and art in ways I have never performed before. What I love about the intimacy at Voltaire at The Venetian Resort is how up-close-and-personal I can be with the audience…a truly modern twist on the performance experience."
This will be Christina's second Vegas residency following The Xperience at the Zappos Theater in Planet Hollywood, which ran from May 31, 2019, to March 7, 2020, when the remaining shows were canceled due to COVID-19.
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