U.S. pop star Ariana Grande has sued fashion retailer Forever 21 for using her trademark style to promote its products without her permission, including adverts featuring a “look-alike model.” Grande is seeking $10 million over claims the brand, and its spin-off cosmetics line Riley Rose, created an online campaign with striking similarities to her music videos, such as 7 Rings, from late last year. The lawsuit, filed in Los Angeles district court, claims the campaign was intended to trick consumers into believing Grande had endorsed Forever 21’s youth-oriented products. “Even a single social media post by Ms Grande can garner fees of several hundred thousand dollars, and her longer term endorsement arrangements command fees in the millions of dollars,” it said.