In Step 11 you made a list of all the characters explicitly named in your revised synopsis. Now list all the characters that your synopsis doesn't specifically name, but that would almost be expected in such a story. Include any additional characters you intend to employ but didn’t actually spell out in your synopsis. Again, list them by role and name if one comes to mind.
Suppose a story is described as the tribulations of a town Marshall trying to fend off a gang of outlaws who bleed the town dry.
The only specifically called for characters are the Marshall and the gang, which you would have listed in Step 10. But, you'd also expect the gang to have a leader and the town to have a mayor. The Marshall might have a deputy. And, if the town is being bled dry, then some businessmen and shopkeepers would be in order as well.
So, you would list these additional implied characters as:
Deputy (John Justice)
Don’t list every character you can possibly imagine – we’ll expand our cast in other areas in steps to come. The task here is no more than to list all those characters most strongly implied – the ones that the plot or situation virtually calls for but doesn’t actually name.
Add these new characters below those in you listed in Step 11. Then, in the next step we’ll add some more!