Instead of tossing Grande all the riches she requested, Forever 21 chose to move forward with a campaign that was clearly inspired by the singer, even though she wasn't actually involved.
Ms Grande said the firm, which has stores in more than 50 countries around the world, approached her in 2018 about endorsement.
In the paperwork filed, Ariana claims that the brand, and the Riley Rose cosmetics company, used at least 30 unauthorized, Grande-related pictures and videos in its marketing campaign.
That's because the brand would not pay Grande enough for her name and likeness, the suit alleges - and her endorsement commands top dollar.
Ariana Grande has a $10 million bone to pick with Forever 21.
Ms Grande is a Grammy Award victor and best-selling singer.
"The resemblance is uncanny and Forever 21's intent was clear: to suggest to the viewing public that Ms. Grande endorsed Forever 21, its products, and was affiliated with Forever 21", the lawsuit says. The number seven logo shown in the pop star's music video also appeared in some campaign images posted on Forever 21's Instagram feed.
The singer filed a lawsuit against the popular fashion retailer in California federal court on Monday, alleging that the company launched an ad campaign that falsely made it look like she was backing the brand, while also claiming that they capitalized off her success and fame to sell their products.
The Instagram posts were deleted by Forever 21 in April 2019.
Grande and her Florida corporation GrandAri Inc. are seeking a jury trial to award actual damages, the disgorgement of Forever 21's ill-gotten profits, and an award of punitive damages to deter Forever 21 and Riley Rose from future violations of her personal and intellectual property rights, the complaint said. They did not indicate how much Forever 21 offered Grande for the deal that fell through.
Riley Rose did not immediately respond on Tuesday to emailed requests for comment.