Two years ago, Jeneane O’Riley self-published her fantasy romance novel, “How Does it Feel?,” an enemies-to-lovers tale about a woman who meets a handsome, unhinged fairy prince. Without a publisher to help market her novel or get it into bookstores, she decided to promote it herself on TikTok.

Pretty soon, TikTok users started posting their own viral reactions to the book, and sales shot up. One post from a reader shocked by the novel’s plot twists got more than six million views. The book hit No. 1 on Amazon.

“That type of free marketing for a small, independent author is unheard-of,” said O’Riley, who later signed a deal with Bloom Books, a romance imprint at Sourcebooks.

Now, with a law banning TikTok in the United States set to take effect on Sunday, O’Riley and other authors are scrambling to keep their networks of fans intact. O’Riley, who has more than 52,000 followers on TikTok, has been urging people to find her on Instagram, Threads and Facebook. But she’s concerned that her close-knit TikTok audience will disperse.

“I worry about the effect it will have on my readers and friends as their sense of community gets destroyed,” she said.

Over the past few years, publishers, authors and booksellers have grown increasingly dependent on TikTok to drive sales. Many of the top selling fiction writers in the United States — including Colleen Hoover, Sarah J. Maas, Freida McFadden, Ana Huang and Rebecca Yarros — owe their success in part to exposure on TikTok.

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