To get a sense of the pent-up demand for fun fashion in larger sizes, see Gwynnie Bee.

In 2013, Christine Hunsicker launched Gwynnie Bee as a subscription rental clothing service specifically for sizes 10 to 32. Her business has been growing 20 percent month over month, and by the end of 2014, she began hearing from several brands that Gwynnie Bee is their No. 1 buyer, purchasing more of their collection than specialty stores such as Macy's.

Gwynnie Bee now carries more than 2,000 styles from 150 brands, and is soon to add Adrianna Papell, Gabby Skye and Melissa McCarthy's new Seven7.

The size range isn't the only point of distinction.

Gwynnie Bee operates like a cross between Stitch Fix and Rent the Runway. Shoppers sign up on the website and add items to their virtual closet. They select from subscription plans that start at $35 a month — the most popular is the three-items-at-a-time option for $79 a month — then begin receiving their selections based on current availability. There's no deadline to return them; notification that an item is on its way back triggers the next shipment. Shoppers also have the option to buy and keep items they love.

The subscription rental format was risky.

"Where you're bringing a new engagement method, you always want a customer who's willing to try those things out, and an underserved market is a good place to start," Hunsicker said. "Women size 10 and above are about 75 percent of the adult female population in the U.S. and completely underserved and not treated well by mainstream fashion. So there were both emotional and economic arguments for it."

Might women dislike the idea of wearing clothes that have been worn by other women? The success of Uber and Airbnb told Hunsicker otherwise.

"If you're willing to let someone else sleep in your bed, there are very few boundaries left around what you're willing to share with people," Hunsicker said, adding that Gwynnie Bee cleans each piece, inspects it three times and hand-packs it for its next steward.

'Plus size' not a dirty word

Rotating a large portion of your wardrobe makes better sense than buying, Hunsicker said, comparing Gwynnie Bee to Netflix.

"You're getting a bunch of joy, and whatever value, and then you're swapping it back in for something that will give you a new kind of joy," she said. "Gwynnie Bee isn't going to replace ownership for a portion of your wardrobe, like your favorite jeans, your favorite black blazer — the things you get relief from. But why buy an asset that mostly sits in your closet?"

Gwynnie Bee has more than 300,000 Facebook followers and more than 11,000 on Instagram. Occasionally a post will criticize the inclusion of sizes 10 and 12 in an otherwise plus size assortment.

"But, one, we're not calling it plus size — we simply say we carry sizes 10 to 32 — and two, plus size is not a dirty word, it's simply a sizing system in America," Hunsicker said. "There's no value judgment that anyone should be making around the number."

Market research shows that women tend to fluctuate in size. Personal experience does, too.

"I'll be a 16 and then down to a 10, typical yo-yoing," Hunsicker said. "Even in a size 2, you experience frustration around fit fluctuations. But definitely as you move up in the scale, availability gets more and more challenging."

Some of Gwynnie Bee's brands, such as Karen Kane, London Times and Taylor Dresses, have extended their size range specifically for Gwynnie Bee. Straight-size brands, such as Corey, have dipped their toes into the plus size market via Gwynnie Bee, too.

Each month the company introduces more than 60 new styles to its members, the majority of whom are size 14W to 24W. Members check in on average once every two days.