What if Harry Potter had ended up with Hermione -- or Draco Malfoy, for that matter?

In the world of fanfiction, where amateur writers spin new tales involving famous characters and other pop culture icons, anything can happen. While it's not as popular as, say, Snapchat or Katy Perry, fanfiction (also called fanfic) has a devoted following of superfans who've generated millions of stories on the internet.

Kids writing and reading: What's not to love? Well, when it comes to fanfiction, where the possibilities are limited only by imagination, there's a little more to the story.

A good portion of the fanfiction on the internet ranges in age-appropriateness from completely mild to nearly soft-core porn. And there are no barriers to reading it. Whether you're a writer or a reader, you'll come across words and images that are graphic.

If your kid is interested in writing fanfiction or just reading it, you'll want to take a look at the various sites and apps, including the most popular ones -- Wattpad, Tumblr, and WordPress -- that they might be using.

Each platform has its own rules, privacy settings, and publishing tools, which you'll want to review with your young writer to keep them safe as they explore their passion.

Review some of the key facts about fanfiction, important tips to keep in mind, and a rundown of some of the most popular platforms:

Fanfiction Facts

Fanfiction writers are fiercely protective. They know their hobby is a little nerdy and less valued in the publishing world. As a result, adherents bond over their mutual love of the subjects of their stories, as well as fanfic in general.

Fanfic is social. What's the point of writing if no one's going to read it? Fanfiction writers enthusiastically share their work and follow other writers. Part of the fun is the community that develops around specific characters, plot lines, authors, and subjects.

Fanfic can be really age-inappropriate. Not all of it is about sex -- but a lot of it is. (Get tips for managing exposure below.)

It could be the start of a career. Authors Meg Cabot (The Princess Diaries and Airhead) and Neil Gaiman (the Sandman series) have revealed that they've written fanfiction.

Devotees are vocal -- and can resort to cyberbullying. While a lot of followers are supportive, the comments, feedback, and fanfic forums can be heated and even cruel.

Fanfiction Lingo

Canon, non-canon/fanon. When stories use the facts of the original source material, it's considered "canon." Fanfiction that introduces new ideas -- for example, imagining Harry Potter as a muggle (when of course we all know he's a half-blood) is non-canon or "fanon." Fanfic writers are divided on whether their work should be canon or whether it's OK to go rogue.

Shipping. Much of fanfiction revolves around Much of fanfiction revolves around shipping , which is the romantic pairing of characters. Often, there's a call from fans to "ship" specific characters -- say, Harry Styles and Bella from Twilight.

Real-person fanfiction (RPF). No celebrity, character, or content -- including YouTube stars such as Shane Dawson and Jenn McCallister -- is off-limits in fanfiction. Videos of famous people reading fanfiction about themselves -- usually mockingly -- are a fixture of YouTube (and often are super cringeworthy).

Check the Fanspeak Dictionary for a complete list of terms.

Fanfiction Tips for Parents

Encourage writing. Writing -- even if the subject matter is a little blue -- is a positive form of self-expression.

Use privacy settings. Each tool offers different ways for users to protect their privacy, from encouraging pseudonyms (which has pros and cons; see below) to restricting who can read your work to limiting comments. Kids just starting out, for example, should use stricter settings, sharing only with known friends. Once kids get familiar with the tool they're using, you can help them ease up on the settings.

Share safely. You can never predict someone's reaction to what you write. Putting yourself out there can make you vulnerable. Not every kid is ready for that even if they think they are. Try to get them to start with a small audience and grow into their hobby.

Talk about sex. Sex, love, and romance are a big part of fanfiction. The tween and teen years are when adolescents start getting interested in sex, and if they like reading and writing, they'll naturally gravitate toward a genre that explores this topic. If they write sexy stuff, ask them to keep it private or extremely limited. Posting it could attract the wrong kind of interest from other users, and sharing it -- say, with friends at school -- may not go over well.

Don't insist on reading your kids' work. If they want to share it with you, great, but if not, let it go. Just check in every now and then.

Make sure kids respect platform rules. Most fanfic services don't allow porn, hate speech, or revealing personal information about living people.

Keep an eye on the fandom. Fanatics can become obsessive. Anything that interferes with your kid's mood, schoolwork, interests, and so on could mean that something is out of whack. Check in to make sure your kid has things in perspective.

Apps and Sites for Fanfiction and Writing

New Moon Girls Online, age 10+. The sister site of the award-winning magazine, New Moon Girls celebrates pro-girl spirit with stories written by and for girls. The content is mostly literary, but contributions include fanfiction. Girls can post questions, contribute to moderated message boards, and read or publish stories, videos, art, and poems, all of which are screened before being posted to the public. The sister site of the award-winning magazine, New Moon Girls celebrates pro-girl spirit with stories written by and for girls. The content is mostly literary, but contributions include fanfiction. Girls can post questions, contribute to moderated message boards, and read or publish stories, videos, art, and poems, all of which are screened before being posted to the public.

Figment, age 13+. Created by two journalists, Figment is a safe space for teens to experiment and get constructive feedback on their work. Fanfiction is only one of many genres you'll find here. Users are encouraged to use their real names instead of pseudonyms, which may account for the uniquely upbeat interactions on the site. Created by two journalists, Figment is a safe space for teens to experiment and get constructive feedback on their work. Fanfiction is only one of many genres you'll find here. Users are encouraged to use their real names instead of pseudonyms, which may account for the uniquely upbeat interactions on the site.

Teen Ink, age 13+. Supported by the Young Authors Foundation, this outlet for teen creativity offers a bit of everything from poetry to nonfiction with some fanfiction mixed in. There's the potential for sensitive or mature subject matter, but the material is prescreened for inappropriate language or content. Supported by the Young Authors Foundation, this outlet for teen creativity offers a bit of everything from poetry to nonfiction with some fanfiction mixed in. There's the potential for sensitive or mature subject matter, but the material is prescreened for inappropriate language or content.

WordPress, age 14+. This tool lets users create their own websites where they can showcase whatever they want. While the emphasis is on first-person blogging, there is plenty of fanfiction. Teens can encounter everything from serious editorials about current events to pornographic images and descriptions of drug use. Parents should talk to teens about responsible online publishing and help them explore WordPress' privacy options. This tool lets users create their own websites where they can showcase whatever they want. While the emphasis is on first-person blogging, there is plenty of fanfiction. Teens can encounter everything from serious editorials about current events to pornographic images and descriptions of drug use. Parents should talk to teens about responsible online publishing and help them explore WordPress' privacy options.

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Tap Chat Stories Funny Texts by Wattpad, age 16+. This app from Wattpad distributes users' stories in the form of text messages. Stories run the gamut, but there is plenty of fanfiction to keep fans coming back for more. You get a small set amount each day for free but have to pay for unlimited access. While the stories don't have the depth of literary works or novels, they're engaging enough to get teens reading. Teens can write and submit their own chat stories, too, giving them a chance to publish their writing. This app from Wattpad distributes users' stories in the form of text messages. Stories run the gamut, but there is plenty of fanfiction to keep fans coming back for more. You get a small set amount each day for free but have to pay for unlimited access. While the stories don't have the depth of literary works or novels, they're engaging enough to get teens reading. Teens can write and submit their own chat stories, too, giving them a chance to publish their writing.