Split personalities are one of the most commonly misrepresented mental illnesses in fiction. This guide is not about accurately representing this condition. Actually, we're kind of focusing on the opposite today! See, as inaccurate as it is to portray split personality as an angel and a demon trapped in the same body, it's still pretty entertaining to read! Trouble is - mostly because it's wildly inaccurate to the point of being nearly offensive - you've REALLY gotta work the entertainment angle to get away with it; it's a pretty overused trope, which makes it more than a little predictable at best, and lazy-looking at worst. That's why I'm here 8D Today we're going over some things you can do to successfully pull off a black & white split personality character: Call it Something Else The simplest way to avoid a bad reaction to your Split Personality character is to not make them a Split Personality character. Have them be a Possessed character, or a Cursed character, or a character with a Familiar. You get to keep your trope, and you're not misrepresenting, dramatizing, glorifying, or trivializing a serious mental problem; everybody's happy! Give some Thought to the Future Assuming that the split is a bad/troublesome thing: is it something that can be fixed? If so, introduce at least the idea of a cure early on and have your character take steps toward it. Watching an evil half be slowly destroyed (or the good side!) can made for an interesting dynamic as the process goes on. On the other hand, if it is something the character is pretty much stuck with, a couple practical matters should be considered: They should have taken steps to make it liveable. The condition can't be so disruptive that they can't have a life in normal society. Break the Mold This trope runs on a Good and Evil dynamic, but any character deserves more depth than that, and yours has a trope with a bad rep to overcome! I recommend completing the Ultimate Character Bio and/or the Character Questionnaire for both sides of this character, but at the very least you should do the Basic one. Make sure you don't just add depth to their character in the bio, too; display it in the roleplay. Show their insecurities, their skills, their fears, inabilities, quirks and preferences; make them into people instead of tokens. Switch it Up You probably saw this point coming, didn't you? It's obvious, but important; if you want to make a tired trope entertaining, it needs to not be tired. Here's a few staple characteristics of the Black and White personality, and some ways you could tweak them! The Good personality is tortured/victimized by the Evil personality It could make a more interesting dynamic if the good personality is indifferent to the morality of their other half, or is in denial of it. Even better if they're not the pure flower they seem to be. The Evil personality victimizes the Good personality Tweaking the morality of the evil personality works, too! Remember that every villain thinks they're the hero; is the Evil personality actually protecting or trying to help the good personality in some twisted way? Are they working toward the good of some bigger picture? Maybe they can even be working together! One personality is aware of the other, regardless of who is in control It could be more interesting if each personality is unaware - or not fully aware - of the other; they could simply "lose time" when the other is in control, and while being moral opposites, not leave such a huge trail of evidence that they were someone else that it's not super-duper obvious to other people.