On a whim one night, Simona Stallone clicked on some Harry Potter fanfiction, and quickly tumbled down a rabbit hole.

Ms. Stallone, a 28-year-old real estate agent and content creator who lives in Toronto, kept seeing posts about “Dramione” all over her feed. People on TikTok were raving about stories set in the world of Harry Potter, written by fans, that imagined a romance between the bookish Hermione Granger and her antagonist, the arrogant bully Draco Malfoy.

As a Harry Potter enthusiast who had always thought that J.K. Rowling should have brought Draco and Hermione together, Ms. Stallone was primed to become a Dramione addict.

Lying next to her sleeping boyfriend, she clicked on “Manacled,” a dark fantasy set in an alternate universe where Harry Potter is dead and the evil wizard Voldemort has triumphed. The story centered on an illicit, morally ambiguous romance between Hermione, a magic-wielding healer, and Draco, a vicious executioner who later holds Hermione captive as a prisoner of war. It had familiar elements from the Harry Potter books, but with a delicious twist — the characters were a little older and a lot hotter. And they were cast in decidedly more adult scenarios.

“Manacled” quickly became her “whole personality.”

“I was fully consumed by this book,” Ms. Stallone said. “I define my life as before and after ‘Manacled’ — you know, how some people are like, before Christ. ”

She got tattoos of imagery from “Manacled”— a constellation on her shoulder and a hummingbird on her ankle. She read the book half a dozen times, and when she wasn’t reading it, she listened to a fan-made audio recording of the story on triple speed to get to the best parts faster. Her friends gave her a three-volume, 1,188 page bound edition of “Manacled” for her birthday. She started a “Manacled” book club and pressed the story on anyone who would listen.

“I made my hyperfixation everyone’s problem,” she said. “I talked about this book nonstop. I made every single person in my life read ‘Manacled.’”

A staggering number of people share her hyperfixation. “Manacled” drew more than 10 million views on the fanfiction site Archive of Our Own, or AO3, and got more than 100,000 five-star ratings on Goodreads. And now a revamped and retitled version of “Manacled,” by the author SenLinYu, is poised to become one of the year’s biggest debuts in romantic fantasy, the genre that is keeping the fiction market afloat.

The new version of the story that so captivated Ms. Stallone will soon be released as “Alchemised,” and the novel’s publisher, Del Rey, is betting that the feverish devotion to its fanfiction predecessor will translate into blockbuster sales. Del Rey has ordered a first printing of 750,000 copies for the novel’s release in late September; translations are lined up in 21 languages.

Besides appealing to hordes of existing fans, “Alchemised” has another advantage: It taps into the raging appetite for romantasy, a subgenre that blends fantasy elements like magic, fairies and dragons with love, yearning and explicit sex.

In a way, the romantasy explosion — driven by the success of blockbuster authors like Sarah J. Maas and Rebecca Yarros, whose series have sold millions upon millions of copies — stems from the legacy of popular young adult series like “Twilight” and “Harry Potter.” Those books molded generations of young readers who have grown up but still crave big fantasy novels — now with a dose of erotica.

“They grew up with the characters, and the stories ended, but there’s still such a huge appetite,” said Leah Hultenschmidt, publisher of the romance imprint Forever. “They’re still hungry for that magical world building, an epic cast of characters and heroism, and maybe they just want it a little spicier.”

Publishers are frantically searching for the next breakout romantasy series. Last year, romantasy sales topped more than 32 million copies in print alone, a 47 percent jump over the previous year, according to Circana Bookscan. Five of the 10 best-selling adult fiction titles this year are romantasies. At the same time, adult fiction sales overall have stagnated.

The kind of romance that’s selling like crazy now — erotically charged genre mash-ups — first took off in fanfiction before publishers recognized there was an appetite for it.

“For a long time, you had to go to fanfiction to find that,” said Anne Jamison, a professor of English at the University of Utah who has studied fanfiction. “Romantasy basically is what fanfiction made.”

What readers seem to be craving more of now is Dramione. There are roughly 35,000 Dramione stories on AO3, and around two dozen of them have more than a million views.

Even as some Harry Potter fans have renounced the books to protest J.K. Rowling’s stance on transgender rights, which has drawn waves of criticism from people who view her comments as anti-trans, stories about the characters have proliferated. Fanfiction and its romantasy offshoots have allowed aging and alienated Potterheads to move on from Harry Potter, without really moving on.

‘The Year of Dramione’

In late June, a crowd of 170 people, overwhelmingly young women, assembled at the Strand bookstore in Manhattan to meet SenLinYu, the author of “Manacled” and its descendant, “Alchemised.” Ms. Stallone was there too, clutching her three-volume bound copies of “Manacled.” She and a friend had driven roughly 10 hours from Toronto to New York City to meet the author and commune with other fans. During the drive, they listened to Ms. Stallone’s “Manacled” playlist of songs that remind her of the characters and setting.

The crowd whooped wildly as SenLinYu took the stage and read a passage from “Alchemised.” “I love you so much,” one audience member blurted out during a question-and-answer session, a sentiment that seemed to be widely shared.

Ms. Stallone sat in the front row and later declared it the “best night of my life.”

Next to her, also vibrating with excitement, was her friend Jessica Sorrentino, another Harry Potter fan turned “Manacled” fanatic, who now prefers “Manacled” to the source material that inspired it.

“It took something precious from our childhood and made it better,” she said.

“Alchemised” is the latest buzzy romantic fantasy novel to emerge from the strange and strangely popular world of Dramione fanfiction. In July, Julie Soto’s romantasy “Rose in Chains,” which was adapted from her viral Dramione story “The Auction,” debuted at No. 1 on The New York Times fiction best-seller list. She was followed by the Harry Potter fanfiction star Brigitte Knightley, whose Dramione-inspired romantasy, “The Irresistible Urge to Fall for Your Enemy,” debuted at No. 2.

The Dramione craze took off during the pandemic, crossing into the mainstream when BookTok influencers discovered the stories.

“People were posting about these fanfiction stories like they were novels,” said the literary agent Alyssa Morris, who christened 2025 “the year of Dramione.”

While it’s illegal to sell fanfiction about copyrighted works, fans wanted copies on their shelves, and a market developed for bound copies with elaborately designed covers that look indistinguishable from real books.

“There’s this whole secret economy of Dramione fanfiction,” Ms. Morris said.

It was only a matter of time before publishers and agents took notice. Now Dramione stories — which come conveniently prepackaged with large and devoted audiences — are migrating from niche corners of the internet to the aisles of bookstores and big box chains.

The fanfiction to romance pipeline was well established before Dramione adaptations came along. E L James became a pioneer with her erotic trilogy “Fifty Shades of Grey,” which began as “Twilight” fanfiction and sold more than 165 million copies. Romance authors like Christina Lauren, Ali Hazelwood and Thea Guanzon, who had all started out in fanfiction, followed.

As more writers cross over from the shadow world of fanfiction into traditional publishing, the lingering stigma and fear of lawsuits has faded. Entrepreneurial writers realized they could adapt and sell fanfiction without violating copyright law if they changed character names and other derivative material. Publishers who had once sneered at fanfiction writers as nerds cranking out “Lord of the Rings” spinoffs in basements began embracing it as free marketing, and then as a talent incubator.

Some authors, including Ms. Rowling, have given fan writers their blessing, though according to her agency, Ms. Rowling opposes stories that put her characters into “obscene” scenarios, since they were written for children. (She would most likely be appalled by the extensive catalog of erotica inspired by Harry Potter, including “Snarry” stories in which Harry and his Hogwarts potions professor Severus Snape become romantically entangled.)

Authors who might have once been coy about writing fanfiction now flaunt it in publicity materials, social media posts and at book signings and fan events.

In an unsubtle wink to Dramione constituents, the covers for “Rose in Chains” and “The Irresistible Urge to Fall for Your Enemy” feature figures that are unmistakable to fans as older, sexier versions of Draco (silver-haired, chiseled face) and Hermione (wavy brown hair, delicate features). Both covers feature artwork by Nikita Jobson, an artist who’s beloved in fanfiction circles for her moody, suggestive illustrations of Draco and Hermione.

Ms. Knightley — who caught the attention of publishers and literary agents when one of her Dramione stories went viral, eventually drawing more than 4.6 million views — described her new novel, about a Hermione-like magical healer and a Draco-like assassin, as an original work that’s “Dramione-coded.”

“Dramione-coded is shorthand, telling readers what sort of dynamic they can expect — in this case, a dynamic involving posh boy and clever girl character archetypes,” Ms. Knightley said.

With “Rose in Chains,” the first in a trilogy, Ms. Soto has also courted Dramione readers, who turned out in droves during her book tour, sometimes bringing copies of her fanfiction to get signed.

Sitting in a Manhattan Barnes & Noble, where she was signing towering stacks of “Rose in Chains” before meeting a crowd of 270 people, Ms. Soto marveled at how much attitudes toward fan work had changed.

“Fanfiction used to feel like it had to be a dirty little secret,” she said.

Now, it’s considered a draw. At a Barnes & Noble in Mansfield, Ohio, “Rose in Chains” was pitched directly to grown-up Harry Potter fans with a large display table sign: “When you ship Draco Malfoy and Hermione Granger, these are the books for you! Dramione Forever!”

Who Needs the Original?

One doesn’t even have to be a big Harry Potter fan to be obsessed with Harry Potter fanfiction. There are people walking the earth who have read book-length works of Potter fanfiction but don’t especially care for the originals. And some of them are even making a career off the Harry Potter fandom.

SenLinYu, 34, who identifies as nonbinary and uses they/them pronouns, first encountered Harry Potter through fanfiction, long before reading the books.

Growing up with six brothers in a conservative Christian household in the Pacific Northwest, the middle child of an evangelical pastor and a former ballerina, Sen was home-schooled and cut off from mainstream popular culture. Harry Potter, which Sen’s parents viewed as un-Christian, was way off limits.

Sen could access the internet for educational research, though, and discovered fanfiction. Despite having no connection to the original books, Sen devoured stories set in the world of Harry Potter and didn’t read the original series until college.

Years later, after graduating from a small Christian college, marrying and having two children, Sen started writing fanfiction late at night on their phone. In 2018, they came up with a twisted love story about Hermione and Draco, imagining Hermione as a healer with magical powers and Draco as her morally compromised lover, and posted chapters under a pen name on A03. When Sen finished the story in the summer of 2019, “Manacled” topped 370,000 words — longer than the longest book in the series, “Harry Potter and the Order of the Phoenix.”

Sen had moved on from “Manacled” by the time it blew up during the pandemic, when TikTok creators embraced it and posted tearful reactions to the story’s devastating twists. Fans made audio recordings and foreign language translations and wrote their own “Manacled” spinoffs. It spawned fan art, T-shirts, mugs and printed copies that are sold on sites like Etsy and Mercari.

Despite Sen’s pleas for people to stop selling bootleg bound editions, which violate copyright law, the internet was soon awash in illicit copies. Third-party sellers hawked copies on Walmart’s website.

“It kept getting bigger and farther out of my control,” Sen said.

In 2022, Sen decided to delete “Manacled,” rewrite the story and publish it. Sen invented a new magic system based on alchemy, created an elaborate world with centuries of history, changed the characters’ names and back stories and reworked the plot, cutting more than 50,000 words, but keeping the structure and transplanting some phrasing more or less verbatim.

Even since Sen removed the fanfiction and told readers that it would be transformed into an original work, “Manacled” still has staunch adherents and rogue copies continue to circulate.

“It breached containment,” Sen said, “in a spectacular way.”

The Shadow of Rowling

On a drizzly evening in July, dozens of young women dressed for a night out stood outside Book Club Bar, a bar and independent bookstore in the East Village. The crowd of nearly 90 people was full of Dramione fans waiting to get into a midnight release party for “Rose in Chains.” They passed the hours until the book drop by sipping purple signature cocktails, taking photos with the author, playing Pictionary and chatting with other fans, occasionally trading tips about the best Dramione stories.

Some brought bound copies of “The Auction” — the original fanfiction incarnation of the story. (Those copies are now harder to find: Ms. Soto deleted “The Auction” from A03 because she didn’t want any spoilers for the new version, but she knows the original is still in circulation. “If your friend wants to send you a PDF, that’s between you and Jesus,” she said.)

Olivia O’Keefe and Margaret Thomas, friends and recent college graduates, came dressed in character in evening dresses, carrying their copies of “The Auction,” and were giddy at the prospect of meeting Ms. Soto. Ms. O’Keefe and Ms. Thomas grew up with Harry Potter and got heavily into Dramione fanfiction after reading SenLinYu’s “Manacled.” The appeal, they said, is in the spicy romance, the nostalgia and the way fanfiction allows them to stay connected to Harry Potter without benefiting Ms. Rowling, whose gender politics they oppose.

“A lot of us found comfort in fanfiction because we could still live in that world without supporting her views,” Ms. Thomas said.

Not everyone agrees that’s possible. Some critics of Ms. Rowling have questioned the ethics of publishing reworked Dramione fanfiction, arguing that engaging with Ms. Rowling’s work in any form, even fanfiction, helps prop up her legacy.

Outrage toward Ms. Rowling has spread to authors who have taken inspiration from her. Last month, Ms. Soto withdrew from a romance convention after the event’s organizers were criticized for promoting her work — a novel that began as Harry Potter fanfiction. Ms. Soto said she’s no longer writing Dramione stories because of Ms. Rowling’s politics. “I stopped interacting with the Harry Potter fandom,” she said.

SenLinYu said writing Harry Potter fanfiction felt like a way to defy Ms. Rowling and reclaim the characters. Still, Sen worries it might look like an endorsement, and isn’t sure about posting more Dramione stories.

“I don’t want it to be misconstrued that I’m trying to promote her or aligning with her views,” they said.

Ms. Stallone — who is planning to be at the midnight release party for “Alchemised” at a Barnes & Noble in New York in September along with an expected crowd of 900 fans — said that despite being “a big Harry Potter fan” when she was younger, she’s now primarily a Dramione fan.

“Manacled” was “a gateway drug,” and now she mostly reads Dramione stories, along with romantasy series by authors like Sarah J. Maas and Rebecca Yarros, she said.

As for the original Harry Potter, she no longer sees the appeal.

“I don’t think I’ll ever be able to read it again,” she said. “I would one hundred percent read a fanfiction, though.”