I'll be curt: I hate fandoms.
Now, I don't hate fans, or even fanboys/girls. Just fandoms. And not all fandoms. Some fandoms are actually pretty cool, and I'd be lying if I said I wasn't a part of one or two. But let's be honest: fandoms can be scary, especially when they're trying to cram themselves down your throat. And so, I've cooked up a list of the five scariest, most militant fandoms that I've encountered.
Honorable Mention 1: Any popular and/or long-running franchise
Doctor Who. Pokemon. Harry Potter. These are cash cows that probably span multiple media, and while the fandoms themselves usually aren't terribly bad, the fact that you'll probably encounter them is. You'll know fanboys or fangirls personally, and they will talk about the work they so love, and you will want them to just shut up about it. Again, the fandoms themselves are usually fairly self-contained and are often very good as fandoms go. They're just very prevalent and there is no escaping them, and a non-fan can easily find zirself on the outs.
Honorable Mention 2: Any fandom that focuses largely on shipping
Sometimes you just want to talk about Avatar: The Last Airbender without having someone ask you whether you favor Kataang or Zutara. And sometimes, you want to be able to mention a romantic relationship without being told that you are wrong for pairing one fictional character with another. The fandom becomes about the shipping, not about the work, and it tends to get annoying to people who are just looking for normal discussion.
5: Star Wars
Star Wars is a juggernaut of a franchise, spanning movies, action figures, books, animated series, video games, a Lego line, video games (yes, more than one) based on the Lego line, TV specials based on the video games based on the Lego line, and countless more media. Chances are, even if you're one of the zero people in the world who haven't seen Star Wars, you're at least familiar with it. As a result, people are going to talk about it. However, most fans of Star Wars are just casual fans. When you run into a hardcore fan, you will know, because they will have a vast amount of knowledge about the Extended Universe that they will be more than willing to share with you any time you're wrong (i.e., not as well-informed) in as smug a manner as possible. Yes, they will tell you you're wrong about a franchise that has more retcons and continuity errors than the Marvel and D.C. universes combined. And again, because Star Wars is something that everyone knows about and any geek will talk about, these people are impossible to avoid.
4: Touhou Project
Touhou Project, or Touhou, is a series of games made almost entirely by one guy (known as ZUN, I believe). They're part of the "bullet hell" genre, which is pretty much entirely about spamming attacks while dodging the attacks your enemy is spamming. And apparently, around 80% or more of the information about the games is based in fandom. That's right. 80%. It's very possible to know more about the Touhou fandom than the Touhou games. There are endless remixes and fanvids and whatnot. Now, while I'm sure that the games are decent, it seems that the fandom is its own separate entity. The fandom isn't about the games anymore, it's about the fandom. In fact, this would probably be higher on the list if it weren't for the fact that I really don't know all that much about Touhou or its fandom.
Ah, yes. The only fandom that I know of where people have been attacked for not liking the books. The Twilight fandom (consisting entirely of fangirls) are people who will defend their series to their dying breath and you are wrong for having an opinion that doesn't match theirs. The shipping wars have actually managed to go mainstream with the "Team Edward" and "Team Jacob" merchandise. It's a ravenous fandom consisting predominantly of mindless preteen girls. Thankfully, due to the cash cow being down to its final drops of milk and the equally ravenous hatedom (who are probably even worse than the fandom), the Twilight obsession finally seems to be waning.
Homestuck's fandom is so fervent about the love for the story that one of their memes is "let me tell you about Homestuck." Let me repeat that: one of their inside jokes is about how they're aggressive jackasses about Homestuck to non-fans. Any fan of Homestuck will inevitably think that it is the Best Thing Ever of All Time (TM) and will instantly gush all over Tumblr or wherever about the latest update. It's one of the more prolific fandoms (especially in terms of memes), and while it's probably not as prolific as Touhou or the number one spot on this list, the sheer militant intensity of the fandom's love for Homestuck and the fact that it's the one I personally hear the most about earns it the number two spot.
1. My Little Pony: Friendship is Magic
Okay, let's be honest. Who didn't see this one coming? There's no way I'd be able to make a list of aggressive fandoms without mentioning bronies? This is by far the most prolific fandom I've ever encountered. And the thing is, I don't get it. Yes, the show is entertaining. By standards of kids' shows and merchandise-driven shows, it's very good. In fact, I'd say that it's at least "good" by the standards of shows in general. But when you really look at it, that's all it is. It's a show aimed at children, so it's going to be simplistic. The plots, the themes, and the humor are all very base (so as not to fly over the children's heads), but the fandom treats it like no greater show could possibly exist. Again, it is a decent show, but there are so many fanvids, so many macros, so many remixes...and the fandom is fervent enough to go mainstream, all for a very simple and base show. I just don't get it.
So that's my list of the top five worst fandoms you could encounter. Again, this is nothing against any of the fans, or even the fanboys/fangirls. Finally, your experiences may vary, and if you have anything to say, leave a comment.