This partnership comes at a time when many retailers, particularly those in the apparel business, have been struggling to draw customers into physical stores. E-commerce champion Amazon is proving to be everyone's biggest competitor, making shopping online more appealing to many.
"The mall space has to change and is changing," retail investment research firm founder Jane Hali told CNBC in an interview.
Mall owners, like GGP and Simon, are looking to restaurants, service-related concepts and grocery stores to bring traffic back to the mall now, Hali said.
"Customers have come to expect lifestyle options at their regional shopping centers," Sandeep Mathrani, CEO of GGP, said in his own statement on the partnership.
The real estate investment trust, or REIT, GGP owns 127 retail properties and is reportedly exploring strategic alternatives, including a possible sale, according to a recent report from Crain's Chicago Business. This, as mall REITs are battling an onslaught of news about retailers' store closures and bankruptcies in 2017.
Another good reason for Forever 21's launch of Riley Rose is the latest boom in the beauty and makeup business, Hali added.
"Beauty has been doing very well in retailing's challenging world," she said. "Millennials obviously enjoy shopping for cosmetics in boutique environments such as Sephora and Ulta ... Riley Rose can be another competitor in this space."
GGP's stock was climbing about 2.5 percent higher Friday, although shares are down more than 12 percent from one year ago.
Shares of Ulta Beauty, a major player in the makeup space, have climbed a whopping 41 percent over the past 12 months.
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