Christina Aguilera, 45, Looks Half Her Age as She Shows Off Her Slim Figure in Sheer Black Outfit at L.A. Event: Photos

Christina Aguilera turned heads in a daring sheer black outfit during a star-studded night out in Los Angeles.

The “Beautiful” singer, 45, attended MISTR’s annual National PrEP Day celebration at The Abbey in West Hollywood on Saturday, October 10, where she showed off a bold, gothic-inspired look.

Aguilera flaunted her slimmer figure as she wore a sheer black minidress made of delicate mesh fabric, complete with black cross details. Underneath, she paired the see-through design with a black lace bra and high-waisted black underwear featuring lace-up details along the sides.

She finished the outfit with nude fishnet tights and dramatic black thigh-high heeled boots decorated with multiple horizontal straps.

The pop star kept her beauty look equally striking, wearing her long platinum-blonde hair in loose waves, smoky eye makeup and a neutral mauve lip. She also posed confidently against the event’s blue backdrop, giving photographers several angles of her outfit.

Aguilera wasn't the only major music star in attendance. She joined Chappell Roan, Charli XCX and Demi Lovato at the annual celebration, which raises awareness about HIV prevention, sexual health and access to PrEP, a medication that can help prevent HIV infection.

Of course, people were floored by her appearance. One person wrote, "She still looking like that. She in her 40s, and she looks like she and Charli can be the same age. That's good for her👏🏾👏🏾👏🏾," while another said, "Christina Aguilera is back in her 20s."

A third person added, "Christina Aguilera looking like she's as young as Chappell 🤯💖✨️."

The event comes shortly after Aguilera enjoyed a sun-soaked Italian getaway with her longtime fiancé, Matthew Rutler.

The singer shared a series of photos from Portofino, Italy, on October 4, giving fans a peek at her stylish escape along the Italian Riviera.

“Who knew Neverland was in Portofino??” Aguilera captioned the Instagram post, adding a string of whimsical emojis alongside Italian flag and ocean-themed symbols.

In one photo, the “Genie in a Bottle” singer posed on a terrace overlooking the sparkling blue water. She wore a colorful halter-style scarf top with pastel pink, yellow and green details, paired with light-wash jeans and dark sunglasses.

Her blonde hair was pulled into a high, slightly messy bun.

Other snapshots captured quieter moments from the trip, including a breakfast spread on a balcony overlooking the coast, a cozy bedroom and a playful photo of Aguilera lounging in bed.

She also included a black-and-white picture of herself with Rutler.

Fans were quick to share their thoughts in the comments section.

“Wow u look amazing,” one person wrote.

Another added, “Must feel so good. How lucky.”

Aguilera and Rutler got engaged on Valentine's Day in 2014. Later that year, in August, they welcomed their daughter, Summer Rain. The singer is also mom to her son, Max Liron Bratman, whom she shares with her ex-husband.

Despite their long engagement, the couple doesn't appear to be rushing toward a wedding.

A source told Us Weekly in 2023, "There are no wedding plans at the moment. [Christina] and Matt are happy the way they are. They’re one of those couples who don’t need a document to prove their love for each other."