As Harry Potter universe grows, some fans wonder: Is J.K. Rowling selling out?

The boy who lived will never die. His creator — and his production team — love him too terribly much.

After J.K. Rowling catapulted teen fiction into a new stratosphere with "Harry Potter," the bestselling book series in history, she conquered Hollywood with an eight-movie film franchise that stands as the second highest grossing.

When the end credits rolled on that final movie in 2011, to casual fans it seemed like Harry's world had come to a natural conclusion — an epilogue sent the now thirty-something characters on their wizarding ways.

But it was far from over. Sunday (at 12:01 a.m., to be precise) marks the latest chapter for Pottermania and its ballooning economy. Fans across the country are slipping into robes and painting lightning bolts on their foreheads to celebrate the release of the book "Harry Potter and the Cursed Child."

Alison Nguyen, president of the Harry Potter Literature Club at the University of Minnesota, said she went numb at the close of Harry's original adventures. "I don't know what to look forward to," she thought at the time.

Fear banished, ahead lay an avalanche of new movies, plays and books.

While many fans are charmed to rejoin the Hogwarts gang, others worry that this expanding list of products could wreck their beloved universe. The new book is being promoted as the "eighth story," yet it's actually the script to the play of the same name now onstage in London. Rowling, a powerful hands-on author, is raising her wand to light the road ahead — but is she just selling out?

So she's not selling out, most fans say, she's just selling.

"This play would never have happened if this particular team had never come to me," Rowling said about "Cursed Child" on BBC Radio 2 last year. "I didn't go looking for this; this found me." (The play was written by Jack Thorne, working from an original story co-written with Rowling and the play's director, John Tiffany.)

Even if Rowling never picked up another quill in her life, fans would continue building her empire, one time-extensive project at time.

There are more than 746,000 fan-created stories on fanfiction.net, in addition to Kickstarter-funded films detailing the back stories of characters, such as "Severus Snape and the Marauders." Conventions rise up and "wizarding bands" wail in bookstores across the world.

The beauty of this particular fandom, said Lori Campbell, who teaches "Harry Potter: Blood, Power, Culture" at the University of Pittsburgh, is its lack of backlash.

Whereas George Lucas cashed out when he sold "Star Wars" to Disney, Campbell credited Rowling for keeping her work controlled and authentic, from e-book rights to merchandising. Fancy some fish and chips at Universal's Hogwarts theme park? They come with tartar sauce and the author's signoff.

But some recent moves leave fans, including Kat Miller, creative and marketing director of fan site MuggleNet, feeling conflicted.

Rowling, for the first time, is publishing an e-book of the screenplay to "Fantastic Beasts and Where to Find Them," the first in a trilogy of films that will begin hitting theaters in November.

The children's book "The Tales of Beedle the Bard" and the original "Fantastic Beasts" textbooks expanded the universe, Miller said, but the screenplay just capitalizes on fans' wallets and excitement.

"That, to me, felt like a money move instead of a passion move, which is something we aren't used to from Jo," Miller said, Jo being how fans address Rowling.

He said he would support new Potter books taking place in an alternative time frame, but otherwise, "I would tell [Rowling] to her face, 'No, that's not canon. Don't play with that.' "

Miller also has something to say about Rowling's marketing "Cursed Child" as the "eighth story." Harry's story is done, Miller said. Leave him alone, if you can.

"Am I going to buy the script? Absolutely. Do I have tickets to see the play? Absolutely," she said. "Does that mean I'm really excited about it? The jury's still out."

In today's entertainment world, goodbye is never forever. Witness Marvel superheroes and "Star Wars" characters. After prequels and sequels dry up, a movie studio may go to another "silo," for example, unpacking a side character's story for a Netflix series or yet another movie, said Paul Dergarabedian, senior media analyst for comScore.

To manage these properties, Warner Bros. hired acclaimed comic-book writer Geoff Johns to oversee DC Comics as its chief creative officer, and the studio just firmed up a team of four senior managers to handle the growing Harry Potter realm.

To Hawk, some of Rowling's tweets seem designed solely to get the fandom all atwitter for Warner Bros., such as when the author tweeted that Ron and Hermione will suffer marital issues.

"What was the point of that?" Hawk said. "It just sparked a fury of Harry Potter debates and everything, which is all good for business."

Rowling declined to be interviewed for this story.

As fans grow and mature, however, so does the franchise.

The University of Minnesota is home to one of the world's largest intramural Quidditch teams; about 165 students play the Potter-inspired sport with brooms clamped between their thighs. Cally O'Neill, team president, said more content will boost opportunities to meet her generation's demands to diversify the series.

For the record, Rowling ruled on this matter with a December tweet: "Canon: brown eyes, frizzy hair and very clever. White skin was never specified. Rowling loves black Hermione" with a kissing emoji.

Real-life Dumbledore's Armies raised more than $123,000 for Haiti disaster relief, then also flexed the fan base's muscle by pressuring Warner Bros. to switch to fair-trade chocolate for park fare and merchandise in 2014.

So fans hold a strong hand, but they would flee without Rowling's stamp of approval, Dergarabedian said, not that he ever expects her to fully sign off.

"To be able to re-evaluate and reinvigorate a brand like this with the original author is pure magic," he said.

Pun intended.