“What is a fan character?”
Fan characters (also referred to as ‘OCs’ –original characters) are unofficial characters created for a particular cartoon/book/movie (in this case, Darkwing Duck). They are created by the fans and often used in artwork, stories, and online roleplaying.
It is not uncommon for fan characters to have a connection to the official characters. Sometimes the fan character is a relative or offspring. They may even be romantically involved with official characters!
Fan characters will never appear in official work, as they are not owned by the company. You will never see a Darkwing Duck fan character featured in the Darkwing comics or cartoons.
Anyone can make a fan character! All you need is a little imagination.