If a book doesn’t have strong side characters, no matter how much I like the main character, I’m probably not going to like the story. Otherwise, it tends to feel like the whole world revolves around that one character, and I’m not as connected to the story that way.
Side characters shouldn’t just be part of the background, they should be just as important to the story as the main character, if not more.
The main character shouldn’t be carrying one hundred percent of the bulk of anything, and if they are, you may want to reconsider how the story is structured. Doing side characters right will make your world and your stories come to life in your readers’ minds, giving it more depth and feeling.
So let’s analyze how to do that.
Each character is the star of their own story
You’re trying to write a world that’s as realistic as you can make it. And no one in real life is going to sit around waiting for a main character to do something. They are the main character from their own perspective, and your side characters should feel the same way. They should disagree with the MC sometimes, have different political views, and have goals outside of what the main character is doing.
I see a lot of side-character issues rising up in characters that play a best friend role. These characters will often only come alive when the MC is around. And their only role seems to be giving advice for the MC’s problems, or needing help from the MC with their own. Never do these characters have side plots or even just stories that run in the background that they can handle on their own, or that the MC doesn’t need to help with (ask yourself this — have you ever imagined what friends your side character has outside of the main character?).
Side characters should be capable in their own right. Look at the cast of Pride and Prejudice. Each character had their own story lines that coincided with Elizabeth and Mr. Darcy, but neither of them had to have much of a hand in any of them, except for the situation of the most urgency. Kitty, Jane, even Georgiana Darcy were their own characters independent of the main ones.
A good test to see if your side characters is strong enough is to imagine if that character could carry a story on their own. I, personally, could easily imagine any one of the Pride and Prejudice cast in a movie of their own, and their characters are interesting enough to enjoy them. Kitty’s naivety and eagerness, Jane’s seriousness, yet light enough to be fun. Any one of them would make engaging main characters.
Try it! Imagine one of your side character as a main character in their own story. The catch is, you have to imagine that person in the same setting they come from. If Jimmy was the main character, the owner of a restaurant, then Sal, his best friend and sous chef, is now the main character, but he stays with his original role. He’s still sous chef and he still has the same life as before. If Sal doesn’t have a very interesting story to you, he may need more development. He may also need more development if his story surrounds the idea of coming out of “his shell” or anything else that suggests he’s going from letting someone else take all the attention to deciding he wants some of it for himself. It could just be his character, in which case it’s fine, but it could also be that you’ve subliminally made him not matter as much as the MC, and feel the need to fix that.
Side characters that have a lot in common with the MC is nice and all, but characters that oppose each other are a touch more realistic to me. A couple characters that are similar is fine, but everyone agreeing all the time doesn’t happen in real life. And characters that argue every once in a while, oppose each other, challenge each others’ thinking, all of this helps characters develop each other. Besides, it’s fun to come up with how those two opposite characters ended up working so well together.
I’m sure you’ve had friendships that, on the surface, made no sense. Polar opposites, nothing in common, whatever. But the friendship still worked. Conflicting characters make for interesting friendships. Create huge differences that they’re able to cross in order to be friends!
At the end of the day, make your characters unique. Don’t make too many of them alike because life is too varied for that. We come across people of all kinds of personality traits and backgrounds, and they should make up your story as well. The mix is actually complimentary.
Take all kinds of iconic friendships in fiction, Shawn and Gus from Psych, Raven and Chelsea from That’s So Raven, Martin Riggs and Roger Murtaugh from Lethal Weapon, all of them are complete opposites. However, they rely on each other for their check and balances. Without their friend, they would be in trouble (well, more than they usually are).
Whether your central side character is only one, or as big a gang as The Goonies, let them all balance each other out. Let them be flawed, but let another character fill that gap, and it’ll create an even deeper bond. It makes them inseparable!
Don’t forget the villains
Antagonists are side characters too, really. Especially the ones that aren’t the main bad guy. They need more of a personality than just “bad”. Let them have different motives for being the way they are. Stories of their own. Again, they should be able to carry a story by themselves (even if it’s a bad guy origin story). This leaves room for all kinds of interesting arcs! Villains that were once a good guy and eventually turned. Or a villain that changes sides. So much more opens up when you go into depth with the villains that make up your story. So much more than when they’re just the “bad guy”.
Here’s a really juicy idea — a villain that had the opportunity to “turn good”, and almost did, but decided not to in the end. Just think of all the emotions you’re tugging on for your readers. You’ll have them pulled in every which way trying to figure out which way your villain character is going to go, they’d be so invested.
If you want more info about how to write a good villain, I wrote a post specifically about that here.
Even the background characters can have a story
Don’t get me wrong, I’m not trying to make you write seven stories from one. But just think about the background story that brings the character to this scene. Even if it’s a cameo, or someone that only gets short camera time. You don’t have to give them an entire memoir, but just think about it for a while. What does their typical day look like? What do they work as? Do they have a family? Kids? A pet? What brought them to this scene? Is this scene different from what they usually do in a day? What do they think of the main character?
If you can make that background character stick to your readers, even for their short appearance, like the cabbage man from ATLA that literally has no name. I mean, just imagine how heart broken we’d all be if he died.
Give your cameo character something we can remember them by! A fascinating story, a trait that makes them memorable (like ruined cabbages), some kindness they extended to the main character or their friends, or even some way that they were nasty towards them.
Make your characters stand out, in general. Your readers will be a lot more invested for it, and let’s face it. You’ll be tempted to write awesome spin offs from them, too.