Fanfiction for TV shows and movies stuck around in obscure paper-based form called fanzines for a few decades before it found its true home on the Internet, where it has since exploded, with millions of new installments every year. It's easy to assume the members of this subculture are just lonely, obsessed kids in their parents' basements or even lonelier, equally obsessed middle-aged women, but the truth is, you've been reading (maybe even enjoying) fanfiction for a long time. And we're not just talking about adding zombies to Jane Austen.

Jane Austen fanfiction first appeared around 1850, and fan stories based on the works of Arthur Conan Doyle and Lewis Carroll not much later. A Sherlock Holmes fanfiction-writing group, the Baker Street Irregulars, started in 1934 and has since had members such as Isaac Asimov and Franklin Delano Roosevelt.

And even these guys were way late to the fanfiction party. Fifty years after the first complete narrative of the semi-mythical King Arthur appeared in a book called The History of the Kings of Britain in 1138, another writer, Chretien de Troyes, rewrote the story and added in his own character: Lancelot, the handsome knight who steals Arthur's love, Guinevere. He also put in a story about a random cup that he called a "grail." Thirty years after that, another guy decided it would be cooler if it was the Holy Grail. Since then, King Arthur has been interpreted by everyone from Mark Twain to C.S. Lewis, and rewrites are still going on 800 years later.

So what's changed over the last few years? The answer is copyright law. Before the 18th century, copyright wasn't really a thing: You heard an interesting story or song or poem and added in your own stuff after the original author caught the plague and died. Even relatively recently, an author's rights to his creation still lasted only 42 years, after which the story passed into the public domain, free to be toyed with and rewritten.

Today, these rights extend to 70 years after the death of the author. Internet fanfiction gets around this law only because no one is making any money off it. Copyright, not any inherent lack of talent, is what prevents fanfiction from reaching a "respectable" non-Internet medium. When the copyright for Lord of the Rings expires in 2050, expect to see publishers stop laughing at Tolkien fans' epic Legolas romances and start giving them book contracts.

He'll be f*****g that Oliphant by 2051.

As you might anticipate from fans who suddenly realize they have the capacity to mold and shape the universe of their favorite stories, most fanfiction revolves around characters boning one another.

Many fans are disappointed when on-screen romance is skipped over or fades out after some tasteful kissing, and they quickly rush to their crumb-strewn keyboards to pound out a scene of physical intimacy in all its details. Often, the choices for character-coupling are so bizarre that it's easier to assume the writers just put all of the characters' names into a hat and pulled out two at random. Simon offers River Tam a soapy massage aboard Serenity, and Buffy discovers it's much more fun to get slain by vampires than the other way around. There don't appear to be many limits in adult fanfiction, even those created in the original movie or show; everyone can have sex with everyone, regardless of their familial relationship, age, sex or species.

So while Harry Potter fanfiction might focus on a romance between Ron and Hermione, it's just as likely to be about Hermione seducing Lord Voldemort, possibly with a few house-elves involved. And in case just reading about that doesn't sear deeply enough into your very soul, these romantic fan fantasies also take the form of "manips" -- erotic photos created by image manipulation:

But once again, you can find fan-written sex right on the bookshelf. Tie-in novels -- books based on movie or TV franchises -- take up a good chunk of any bookstore's shelf space, and yes, they're loaded with lovin'.

There's the official Star Trek novels detailing the offscreen love affair between Counselor Troi and Commander Riker. Sometimes it's a romance that wasn't even mentioned in the original; a book published in 1985 featured heavily implied homoeroticism between Spock and Kirk. It's not just Star Trek either: The Star Wars Extended Universe novels pair off every character that was still single at the end of Return of the Jedi, sometimes more than once: Lando Calrissian, Luke Skywalker, Wedge Antilles and even Grand Moff Tarkin are all given life partners.

What happens on the Death Star, stays on the Death Star.

Indiana Jones has racked up no fewer than 21 flings, most of which were introduced in his many tie-in novels. The number would have been higher if it weren't for George Lucas, who is famous for purging tie-in novels of sexual content in order to keep his younger audience. We assume that this was done by modifying the text so that Indy's female partners seduced him first.

When work enters the public domain and creators are too dead to intervene, famous works of fiction quickly descend into feverish dick-festivals. The Wizard of Oz fanfiction novel Wicked is famous for its Broadway version, but the original book includes multiple sex scenes and at least one long, awkward section involving inappropriate relations with a tiger. Wicked's author also grittily rebooted Snow White, adding in copious incest, pedophilia and other stuff that probably only gets worse when a roomful of dwarfs are involved. Neil Gaiman did something similar with the same story. In fact, multiple authors now make their living solely from erotic rewrites of fairy tales and other public-domain tales, providing desperate readers with their much-needed Sleeping Beauty erotica hit.

Awwww yeah.

At least those guys are sticking to text form. When this fan-created debauchery rises up in screenplay form, it's guaranteed to infiltrate your life. There are the people who made a Hamlet movie and decided it would be cool to have Mel Gibson dry-hump his on-screen mother, and the Phantom of the Opera director who re-imagined the Phantom as a well-muscled emo who keeps losing his clothes (NSFW). Just about every book translated to film and with a romantic scenario shoehorned in at the expense of the original plot is closer to fanfiction than an adaptation.

In the last decade, the most popular RPF targets were members of boy bands and actors from the Lord of the Rings trilogy. According to the Internet, every single member of the previous two groups has boned every single other member and in fact is probably boning them right now. Some RPF fans have even taken their hobby further, insisting that their stories are based on reality and that the celebrities in question are romantically involved. For this reason, even fellow fanfiction writers view RPF authors as strange.

But once again, the Internet quarantine separating RPF fans from the rest of humanity not only isn't working, it was never there to begin with. For a start, there's the fact that if the celebrities in question are dead, making them bone each other is not called "Real-Person Fiction." It's called "historical drama." Somewhere, right now, there's an actor winning an award for starring in one.

Probably Daniel Day-Lewis.

And non-Internet RPF has never been limited to the deceased. In a trend that started in the 1920s and lasted a good 50 years, books known as "authorized editions" featured stories about celebrities such as Judy Garland and Roy Rogers doing everything from solving mysteries to overcoming romantic entanglements.

RPF was also the rage in teen magazines, which in the 1970s openly published fiction written by fans about their favorite stars, complete with illustrations.

In the 1980s, there was a series of mysteries about Eleanor Roosevelt solving crimes in the White House. Around the same time, Alan Moore and friends openly based comic hero John Constantine of the Hellblazer series on musician Sting. And recently, horror author Poppy Z. Brite added Internet-style perversion to the mix with a book about barely-disguised members of the Beatles boning each other. Meanwhile, the rest of us catch up on tabloids, which mostly consist of rumors about famous people boning each other, often with detailed pictures and "eyewitness" commentary.

Yeah, this is pretty much what we'd imagine an orgy with the Beatles would look like.

Of course, fanfiction writers don't limit themselves to the characters of their own universe. You have "crossover" fan fiction where, say, the CSI: Miami crew could end up enlisting the help of Buffy the Vampire Slayer to identify a forensics clue, or Harry Potter could meet Jacob Black in the forest and fall in love under the moonlight.

You know who else likes to write that kind of ridiculous mashup? Hollywood screenwriters.

"OK, so how about Voldemort and Hitler decide to open up a bed and breakfast in Fraggle Rock?"

Hell, television has been doing crossovers so often that they're cliche. A detective from Law & Order appeared on Arrested Development, CSI visited Without a Trace, characters from The X-Files turned up on Cops, and Lurch from The Addams Family popped up on the old Batman show. Syfy Channel shows Warehouse 13 and Eureka went further, making two characters from the separate shows fall in love. It's also around in movies: Alien vs. Predator, Freddy vs. Jason, and even Disney and Warner combining in Who Framed Roger Rabbit. The comic world has given us equally strange crossovers: Spock fighting Wolverine, Lara Croft facing off against the Wolfman and Dr. Doom teaming up with the Decepticons. And of course, there's Batman and Superman's erotic crossover:

Marvel and DC also did something far weirder than even Internet fans ever came up with: combining separate fictional characters into one. So Wolverine and Batman were put into a blender to create Logan Wayne, the Dark Claw:

Once again, the only thing here holding back an even bigger, more perverted wave of crossovers is not restraint or taste, but legality. The creators of Freddy vs. Jason wanted to end the film with both characters going to hell and meeting Pinhead from Hellraiser. They couldn't because they didn't own Pinhead's character rights, not because a producer looked at it and said, "No way; that sounds like something you would find at the edge of the Internet."

The "Mary Sue" is perhaps the most infamous character type in fanfiction. A Mary Sue is a thinly veiled representation of the author, or more accurately, the person the author wishes she could be. Her main characteristic is her utter amazingness, which is so strong it creates a kind of black hole that sucks in the established personalities of the characters around her.

"I don't know what I love most about you, Raven: The fact that your eyes constantly shift in hue, or the fact that you're secretly a half-dragon survivor of domestic abuse."

Wise characters are baffled by the Mary Sue's superior intellect, emotionally distant men cave in and fall in love with her, cold characters are impressed by her tragic past. She usually features a striking appearance and unusual name and spends her days surrounded by people telling her how wonderful she is.

Mary Sues can be men, too. One appearing in the original Star Wars trilogy, for example, could easily outshine Yoda in the Jedi arts and would have blown up the Death Star himself, except that he already used his wiles to talk Anakin out of being evil. One step down from a Mary Sue is self-insertion, where a fanfiction writer doesn't even bother to disguise his character behind a better-looking mask. Instead, he simply writes himself into the story, like this 15-year-old boy who is mysteriously transported to Pandora and feels himself falling for a seductive Na'vi woman as soon as he gets there.

"My people are all about acne."

It's the literary equivalent of playing pretend, but for adults, and usually based around sex. In other words, it's long-form masturbation.

But don't laugh; by every account, a writer of Mary Sues is now one of the richest authors on Earth. The Twilight novels by Stephenie Meyer fail the Mary Sue Litmus Test miserably: Main character Bella Swan is so charming and attractive that a vampire who has remained a virgin for a century instantly falls in love with her, and several other boys fight him for the privilege. If that's not clear enough, another Stephenie Meyer novel features a protagonist named "Melanie Stryder." Too on the nose?

It must be hard for her to do all that writing one-handed.

Another popular book series, the Millennium trilogy by Stieg Larsson, centers on a Swedish journalist whose life mission is exposing corruption. Coincidentally, this was also exactly what Stieg Larsson did. His fictional version, however, is also fabulously rich and talented, admired by many important people and constantly being seduced by beautiful women, including a former abuse victim whose fear of men is cured by his boner.

There's also the young Star Trek: The Next Generation character who routinely uses his extraordinary talents to save the lives of older, experienced crew members and who is even named after series creator Eugene Wesley Roddenberry:

This self-insertion has been going on for centuries. Dante's Inferno has Dante meeting his dead hero, Virgil, and then running into a bunch of his enemies, who not only admit that they were in the wrong but are actually now suffering eternally in hell. Agatha Christie had a female crime novelist show up to help Poirot with his cases. Stephen King, Robert Heinlein and Geoffrey Chaucer all turn up in their own writing to have adventures and prove to a bunch of fictional people how awesome they are.

Ultimately, the Mary Sue scenario is just fanfiction taken to its logical conclusion, because we are all die-hard fans of some fictional universe we'd love to see and experience, but we are even bigger fans of ourselves. The Mary Sue allows everyone the opportunity to shed the character flaws and limitations we suffer through daily while simultaneously transporting our better selves to a utopia where, if we're very lucky, we have hard, fast sex with Sonic the Hedgehog.

Read more from C. Coville here.

For more on fanfiction, check out The 5 Most Baffling Sex Scenes in the History of Fanfiction. Or learn about some fiction that came true in 6 Eerily Specific Inventions Predicted in Science Fiction.