A question you often see on writing forums and the like involves just how many characters you’re legally and morally allowed to have in a story. I responded to this weird obsession with an acceptable number of characters a few years ago with an article in Writer’s Digest concerned with the fact that very often a manuscript that isn’t working is suffering from too many characters. And while this is absolutely sometimes the problem and I stand by that article, writing isn’t a science, friend. It’s a big mess of superstition, imagination, and magic.
As a result, despite the fact that having too many characters is sometimes the problem, inventing new characters is sometimes the perfect solution to myriad story problems.
Make Room! Make Room!
Too many characters is a problem for Future You, with their completed novel and their insufferable smugness because they completed a novel. Worrying about having too many characters before you’ve actually completed your novel is like worrying whether you’re planning to use too many nails when building a house—you have to wait until the house is finished to make a judgment call.
Because a new character can solve problems. Granted, this is also what leads people into trouble, because every time they have a problem they invent a new character to solve it, and before you know it you’re a 70-year old fantasy writer trying to resolve the arcs of like 15,000 characters in two novels. But there’s a reason pro writers get into character trouble in the first place: Characters solve problems.
So in the Draft Zero stage, why not create characters with abandon? Characters can fill plot holes, provide exposition, and do plenty of other work for your story. And you can always eliminate them later, either by wholesale deletion, or by combining one or more characters doing work into one. Of course, you could also solve plot problems by giving an existing character a new role, but this leads to a parallel problem—over-busy characters. Which solution works best for your story is entirely up to you.
The point is, just as there’s no definitive rule about having too many characters, there’s isn’t a rule on minimum numbers of characters, either. Create them, delete them, combine them and split them at will. You can always go back and make some corrective adjustments later in the writing process.
I also like to create throwaway characters based on people I know IRL and then kill them off in creative ways when the IRL people annoy me. I’m not saying that’s a healthy approach, but it sure is fun.