(Washington Post illustration; iStock)

Imagine that you’re an 18-year-old Army wife with no working car and no furniture. Imagine that you just moved from Ohio to Texas, where you have neither friends nor plans for the future.

Imagine that you’re scrolling through Instagram one day when you chance upon a series of funny One Direction memes. Imagine that you begin to make the memes yourself, pairing pictures of the band with short, speculative stories. You make hundreds of these memes — thousands of them — before you sign up for an account on the writing platform Wattpad. You’re 24 by now, and you have lots of free time. Your husband is stationed in Iraq.

Imagine that your One Direction stories become popular. Popular beyond your wildest dreams. Imagine you get a phone call from a major New York publisher and later from an agent who wants to make your book into a movie. Imagine you’re asked to spearhead a collection of “imagines,” this nascent genre of Internet fiction that you’ve helped pioneer.

Anna Todd has imagined thousands of stories — but this particular tale is real.

“Wow,” said Todd, now 27, who headlines the 600-page tome of “Imagines” that Simon & Schuster’s Gallery Books imprint released Tuesday. “The publishing world really is ready for this.” Finally.

What remains to be seen is whether the wider offline world will embrace the genre Todd and thousands of other writers have spent the past six years developing: a sparkly splinter sect of traditional fan fiction that is devoted entirely, and unapologetically, to teenage girls’ celebrity fantasies.

Born in Twitter’s frothy Justin Bieber fandom in 2010, and incubated on sites like Tumblr and Wattpad, “imagines” vary profoundly — but generally obey a few genre conventions. They’re always written from a second-person point of view, the better to put their reader in a starring role. They’re usually chatty and underproduced, a product of their social platform. And they typically feature a real male heartthrob, typically shorn of his IRL vices and recast in the model of the prime-time teen soap boyfriend. In the world of “imagines,” even the Biebs acts like a latter-day Disney prince.

This new collection, the work of 34 popular Wattpad authors, includes the tale of a budding drama-camp romance between Zac Efron and, well … “you.” Michael Clifford, of 5 Seconds of Summer, takes you to prom and dances the tango. There’s even a story in which you, an obsessive writer of Dylan O’Brien fan fiction, meet the “Teen Wolf” star after his lawyers spot your work. Naturally, O’Brien assures you it isn’t creepy, begs you to keep writing, and even buys you a drink afterward.

“Imagines are all about wish-fulfillment,” stresses Anne Jamison, a professor of English at the University of Utah and an expert on fan fiction. “They’re all about self-insertion.”

Their target reader, she adds — not surprisingly — is typically “very young”: girls in their preteens, teens and early 20s, the same ones who fuel boy-band fandoms. Wattpad, which has amassed a library of 330,000 imagines, estimates that 75 percent of its readers are female and 80 percent are under 30. Tumblr, which logged more than 20 million posts tagged “imagines” last year, also skews toward young ladies.

Historically, of course, this is the very demographic that’s been silenced and stigmatized for its passions. But in the comments sections of Wattpad stories, or the repost chains on Tumblr, the validity of girls’ interests and feelings is assumed from the beginning: They trade imagines among themselves, riffing and iterating, requesting personalized stories to act out their individual fantasies.

“They make you feel less insane for loving something,” said Erin Gross, the founder and publisher of the site Fangirlish, who has read and loved “Imagines” already. “They make you feel like you don’t have to be ashamed of the things that you like. It made me see I’m not alone. … It’s like finding your tribe.”

And yet, the publishing industry’s formal recognition of that tribe will not be without its critics — ranging from disapproving feminists to old-school devotees of fanfic. Jamison, the University of Utah professor, points out that established fan-fiction communities, like Archive of Our Own, have long eschewed both wish-fulfillment and monetization; their work is Serious Literature, prefaced wholly on writerly passion.

The Wattpad model, which Jamison calls “the Facebook of fan fiction,” flips that inside-out: The 10-year-old start-up runs paid ads next to the stories that millions of writers pump out free, and this book — pitched to Simon & Schuster by a Wattpad executive — also makes the site money. Just this week, Wattpad announced the launch of a division called Wattpad Studios, which will “partner with the entertainment industry to co-produce Wattpad stories” for print, film and TV.

“I do think it could be problematic,” Jamison said. “There’s a danger of exploitation, when the writers are so young and Wattpad is acting as their agent.”

On top of that, there’s the much-debated Disney Princess effect: Maybe it’s bad for girls to grow up worshiping these stereotypes of women and relationships. Some imagines do depict platonic adventures or female friendships, as in my personal favorite from this collection, “Taking Selfies and Overthrowing the Patriarchy with Kim Kardashian.” (It’s set in a dystopian future where selfies are illegal, and Kim turns to you — a disgruntled Best Buy employee — to help her take them.)

Still, the most popular imagines remain those preoccupied with heartthrobs and meet-cutes, boy-banders and first dates — the awkward girl elevated to notability by the attentions of an acclaimed would-be mate. There’s a difference, in other words, between empowering teen girls’ fantasies and perpetuating the ones that have been foisted on them. Which do imagines do, ultimately? It’s a difficult, and yet unanswered, question.

Todd has faced this sort of criticism before: about her imagines, but also about her best-selling “After” series. That story details the romance of a college girl named Tessa and a moody, depressive, oft-abusive Harry Styles — styled, in the print books, as “Hardin Scott.”

“When people ask me questions like ‘where’s my Hardin,’ I’m like — ‘no no no,’” Todd said. “If I were Tessa, I would not stay with him. This isn’t supposed to be a dating manual.”

When you consider how young many of Todd’s readers are, it seems inevitable that some will take her stories as instructive. But Wattpad hopes more girls will be inspired by Todd herself: proof positive that anyone can tell her story online and find an audience for it.

“This is unique to the Internet,” said Ashleigh Gardner, Wattpad Studio’s head of partnerships, pointing out that thousands of fans created this genre from the bottom-up, themselves. “You can’t go to the bookstore and ask for the ‘imagines’ section.”

You couldn’t until very recently, at least: “Imagines” is now stocked in most major bookstores’ romance departments. Even before the book was officially released Tuesday, there were reports of zealous readers begging or bribing stores for early copies of it.

Liked that? Try these!