What Is the A/B/O Trope?

Maybe you’ve seen some of your favorite fics labeled with the term. Or maybe you follow someone on social media who talks about “a/b/o.” Whatever the case, you’re wondering, “What is the a/b/o/ trope anyway?”

If so, keep reading.

What Is the A/B/O Trope?

No matter where you heard the term for the first time, “a/b/o” is kind of confusing without context. If you see it on a fanfic from a favorite writer, you might click into it anyway, but you could end up having more questions than answers.

So, what is the a/b/o trope?

Simply put, this is a worldbuilding trope. The “a/b/o” stands for “alpha / beta/ omega.”

Some Notes on Terminology

A/b/o is also called omegaverse. That term is a little clearer, in that it tells you this is a “universe” with “omegas.”

You may also see tags that use “a/b/o dynamics” or something similar. This is the same idea. It just means that there are certain relationships between alphas, betas, and omegas within the world. Those “dynamics” govern the worldbuilding.

It’s important to note that you should use a/b/o or A/B/O, with the slashes. Never use “abo,” which is a slur for Australian Aborigines. Even capitalizing it, as “ABO,” is sometimes considered problematic.

What the Heck Are A/B/O Dynamics?

In worlds that use the a/b/o trope, there are usually characters who are alphas, betas, and omegas. This is sometimes called a “secondary sex.”

In these worlds, reproductive function is tied to a character’s status as alpha, beta, or omega. Alphas are usually (hyper) masculine, being possessive and jealous of their “mates.” Omegas are more submissive, usually exhibiting more “feminine” behavior.

Betas may be completely “normal” or they may be infertile. In some omegaverse stories, they’re completely absent. It depends a bit on what the writer is doing with their world.

What’s the Difference Between A/B/O and Biological Sex?

Nothing much, actually, although many writers will tab a/b/o status as a “secondary sex.” So, in many omegaverse stories, a character is still “male” or “female,” but then they’re also alpha, beta, or omega on top of that.

This explains the existence of male omegas, which is the usual function of omegaverse. Male omegas can get pregnant and give birth, even though they’re still “male.” Many writers will give them differential physical characteristics, especially when comparing them against alpha characters.

Alphas are usually hyper-masculine, so they’re big, burly, and ultra-possessive. While omegas have heat cycles, the alphas will react to an omega’s pheromones.

Betas, if they appear, may not have exaggerated physical traits. They may not be affected by omega pheromones, or they may only be minimally affected. In some cases, they’re simply “normal” people. In others, they may not be able to reproduce, which is why they’re unaffected and sometimes uninterested in sex. Some writers don’t include betas at all.

What’s the Difference between Omegaverse and the A/B/O Trope?

The answer here is “nothing.” The two terms are interchangeable. Some people may argue that the two are used to indicate slightly different things, but a hard division hasn’t really been established.

How Did the A/B/O Trope Get Started?

The a/b/o trope is generally accepted to have started in fanfic circles. One of the first is an RPF fic from Supernatural fandom. The roots of the trope likely go back further.

We can see some use of “alpha” and “omega” terminology in werewolf romance novels from the mid-2000s. Werewolves were popular at the time, thanks to Twilight and later Teen Wolf, which is why the terminology probably settled on “alpha” and “omega.”

There has been a prevalent myth since the mid-20th century that wolf packs have a leader, known as the alpha wolf. The leader often has “seconds-in-command,” known as betas. Betas will sometimes challenge the alpha for dominance in the pack.

The “omegas” of a/b/o fiction don’t exist in wolf pack theory. More than that, though, the wolf pack theory has since been disproven. The study was done on captive wolves, who often display different behavior than wild ones.

Wild wolf packs are usually parents and their pups from various years. There is no “alpha” leader of the pack, although we really like that idea.

At any rate, this wolf pack myth has been around for quite some time, and even though it’s wrong, people still use it and believe it. When they were imagining how werewolf packs might operate, the “alpha wolf” theory was adopted.

That, in turn, leads us toward the a/b/o trope, although there are quite a few twists and turns in the story from there.

Why Is the A/B/O Trope Popular?

The a/b/o trope incorporates a lot of things fanfic and romance readers like to see. One, it gives the “alpha” characters an excuse to act like alpha-holes. Possessive, jealous, and even abusive behavior is often romanticized in novels and fanfic alike, and being “an alpha” gives the character license to be a dick.

The a/b/o trope also allows some people to explore gender roles and internalized misogyny. It’s interesting to put an ostensibly male character into a hyper-feminized role. The worldbuilding in omegaverse is often dystopian for that reason.

Of course, the biggest reason it’s probably popular is because it creates a flimsy excuse for banging. Omegas going into heat is a great prelude to get your fav fanfic couple to hook up, even if they normally hate each other. It can function a bit like the “fuck-or-die” trope.

As noted, it also works great for werewolf fiction. Other people have pulled it into the ever-popular paranormal romance category via other shifters (like bears and werecats, among others), and other creatures, like demons and vampires.

Some people also posit that it’s a trope that allows for exploration of trans identities. It’s also a vehicle for the mpreg kink, although these latter reasons may not speak to its popularity. After all, they’re not very convincing when we consider how omegaverse has been adopted in the world of het romance.

The A/B/O Trope Is Not Universally Loved

Even if the a/b/o trope seems to be everywhere these days, it’s important to remember that it’s not universally beloved. It is very much one of those “YMMV” things.

Some people absolutely love the trope. As a writer, I love it for its flexibility in worldbuilding. As a reader, I like it as shorthand for the kind of worldbuilding I can expect (as well as the possibility for mpreg in any m/m story). I’m a sucker for dystopias and angst, so I might be a bit biased.

But not everyone loves a/b/o. You’re just as likely to see people bashing it as you are seeing people love it. Some people are simply neutral on it: they’d read it if it was from a fav author, but it’s not necessarily on their auto-buy list.

The a/b/o trope was one that generated a fair bit of division on a poll about fanfic tropes. People who love it, really love. Those who don’t like it? They really hate it, to the point they’d actively avoid fics with the label. They were not excited at all to see a/b/o tags on fics, and they felt strongly about those kinds of stories. In fact, the a/b/o trope was one of the more hated fanfic tropes in the poll.

Yet … someone has to be writing omegaverse fiction for it to get any hate. The proliferation of fics and even original fiction in the indie publishing sphere means that there is a group of people who love a/b/o fiction enough to write it—and a group of people who love reading it. While there may be some overlap between those two groups, there’s definitely an audience.

Learn More about the A/B/O Trope

This is just a quick post to answer the burning question about what the a/b/o trope even is. If you want to go deeper, I’ve written quite a few different articles on omegaverse, exploring many different aspects of it. Here are a few you might want to check out:

• Omegaverse FAQ
• Alpha Females in Omegaverse
• Who Invented the Omegaverse?
• Why Do We Love ABO So Much?
• What the Heck Is the Omegaverse?

There are others kicking around, but those are pretty good primers.

Looking for Omegaverse Fiction?

A lot of my works make use of the a/b/o trope. If you’re looking for m/m romance or mpreg novels, then you might want to check out the Omega on Top series or a book like Evan and the Alpha.

Plenty of other authors write omegaverse fiction. The Fated & Claimed 2 anthology, which is due out in December, is full of m/m romance, omegaverse, and mpreg stories.

Writers like Leta Blake and Sienna Sway are also using the a/b/o trope to great effect. Other writers in this sphere include Zelda Knight, Sophie O’Dare, Hawke Oakley, Lorelei Hart, Colbie Dunbar, Ava Beringer, Susi Hawke, and many, many others. There are also plenty of writers who are working on het romance that incorporates the omegaverse trope.

Finally, there is always, always fanfiction. Fandom is where the a/b/o trope was born and codified. Plenty of fic writers are familiar with it and use it across a wide variety of fandoms. While some fandoms are smaller than others, almost all of them will turn up a couple of a/b/o fics.

So, now you know the answer to “what is the a/b/o trope?” You’ve learned a bit about the basics of the worldbuilding, and you have resources to dive deeper if you want. You also have some ideas about who is writing, where, and what you can find. And that, of course, means you can decide whether or not a/b/o fiction is something that you like—or would prefer to leave behind.