Victoria's Secret's image is under pressure.

The brand currently controls 35% of the lingerie market and has posted quarter after quarter of same-store sales growth.

But Victoria's Secret has recently fallen on hard times.

Several key Angels, including Karlie Kloss and Doutzen Kroes, have left the brand. Start-ups like AdoreMe are poaching top designers and offering similar products at cheaper prices.

Plus-size customers are petitioning executives to offer larger sizes. And Lane Bryant took aim at Victoria's Secret's models in a recent ad campaign.

"Like Abercrombie & Fitch, Victoria's Secret is in real danger of losing its relevance amongst women as the brand is labeled sexist and stodgy," branding expert and University of Southern California professor Jeetendr Sehdev told Business Insider.

Abercrombie & Fitch ruled the teen sector for years but lost its footing when it failed to adapt to fast-fashion competitors like H&M and Forever 21. Abercrombie was also criticized for excluding plus-size customers and minorities in its stores.

"Victoria's Secret needs to stop hiding behind dazzle and dated '70s concepts such as 'Angels" and the 'Fantasy Bra,' and start having a real conversation with women," Sehdev said.

The brand famously hires 10 famous models to represent its brand as "Angels." It also spends millions of dollars on a televised fashion show, complete with diamond-encrusted bras and performances by Taylor Swift.

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"The dazzling and over the top fantasy positioning is simply alienating to the modern day sophisticated and complex young woman," Sehdev said.

As consumers' opinions of beauty change, Victoria's Secret seems outdated.

The brand faced widespread backlash for its "Perfect Body" ad last year, which featured a row of stick-thin Angels dressed in lingerie. Customers complained that Victoria's Secret was promoting false stereotypes of beauty.

The company eventually apologized for the ad.

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Consumers are also pressuring Victoria's Secret to offer larger sizes.

The largest panty size it offers is XL, or equivalent to a size 16. The fashion industry defines plus-size clothing as sizes 12 to 24, though many retailers offer up to a size 28 to meet demand.

Bra sizes are inconsistent. Some styles are offered up to a D, while others go up to a DDD.

Still, many women feel they don't have a good selection at Victoria's Secret.

"My money and my credit are good enough for them, but the fact that I can only buy items like perfume, lotion, and body spray sends the message that my body is not," said Dana Drew, a California woman who launched a petition against the brand. "Every year I watch the Angel fashion show and would love to purchase the items I see on my screen but can't because Victoria's Secret doesn't sell plus sizes."

Plus-size brand Lane Bryant took aim at Victoria's Secret in a new lingerie campaign called "I'm no angel."

Lane Bryant's ads aim to "celebrate women of all shapes and sizes by redefining society’s traditional notion of sexy with a powerful core message: ALL women are sexy," the company wrote in a news release.

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