Making a Bad Character Likable
Turning a bad character into a likable (and even good) character is all about doing the following, or any of the following that you can:
1) Build Some Weak Spots into Their Armor
Few villains are 100% evil. Many have little cracks in their villainous exterior through which little snippets of light can shine. Undying affection for their little lap cat, devotion to the care of an ailing sister, love of their children, showing mercy at unexpected times, or having a line they would never ever cross. These all help the reader to see that good is possible with this character.
2) Give Them a Sympathetic Motivation
Why does this character do the bad things they do? Is there anything even the slightest bit understandable or noble in what drives them? Look at Severus Snape, for example, He was not a super likable guy, but it turns out he had a really noble motivation. Another favorite example is Theon Greyjoy from GoT/ASoIaF. He did some hideously awful things, but he did them trying to win back his place in the family he was torn away from as a child, through absolutely no fault of his own. When you realize that he was essentially family-less in a world where name and family are everything, it was hard not to feel a little sorry for him. Especially after everything he went through as a result…
3) Put Them Through the Ringer
Few things are better for paving the road to sympathy than to have a villain or bad character get a taste of their own medicine and see how much it sucks. When a villain or bad character becomes the victim, you have the opportunity to show their human side.
4) Give Them Their Moment of Realization
When they’re at their lowest, it’s a great time not only to show their humanity, but also to show that they’re aware of who they are and what they’ve done, and that they aren’t proud of it. If they have a noble (or at least understandable) motivation, they can double down on that, but it helps the reader to see that they aren’t enjoying it, and aren’t bad for the sake of being bad. If you want them to turn good, or if they really need to win the respect of another character or the reader, consider giving them that moment of realization that they want to be good, and showing that they’re committed to working toward that.
5) Give Them Redemption
Maybe your character is a contract killer, but maybe they choose not to go through with a contract once they see their target is caring for elderly parents. Maybe your character is a robber, but maybe they make a substantial donation to some worthy cause. Some sort of sacrifice–something that creates a loss (however small or large) for themselves on behalf of someone else is sure to win kudos from the reader. Think of Ebenezer Scrooge, the old miser, parting with lots of money to buy gifts and a Christmas goose for the Cratchit family after making Bob work every Christmas. Or, the Grinch returning all of the things he carefully stole from the Whos down in Whoville and embracing their holiday spirit. This redemptive action, big or small, shows the reader (and the other characters, too) that this person has changed, or at the very least is redeemable, which makes a big difference.