Unfortunately, these are a few-and-far-between occurrence. This being so, I figured I'd go and give credit to some of the cartoon shows that feature gothic or alternative characters. Feel free to add in more in the comments if I don't mention them.
First up is Gaz from one of my favorite shows "Invader Zim." Gaz is the d
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elightfully dark sister of Dib, a big-headed kid who's all about the paranormal and is the only person who sees Zim for the alien that he is. In almost every episode that she's featured in, Gaz makes some threat or other towards her brother or Zim or just random annoying people who dare to cross her path. Although she never lets on that she knows about Zim, she doesn't seem to particularly care whether or not the human race gets destroyed in one of his horribly-planned schemes.
Next we have Sam, short for Samantha, from "Danny Phantom." And fun fact, not on
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ly is Sam the designated goth of the show, she is also the resident ultra-recyclo-vegetarian. On more than one occasion she fights with both Danny and Tucker over her eating habits and environment protection attitude. She's also very smart and well-informed. More often than not, she winds up spinning Danny and Tucker in circles from all the information she gathers about a situation. And she knows how to stand up for herself against even the bitchiest of the popular girls, Paulina, who everyone adores and admires.
Now we come to a character called Raven from the show "Teen Titans." You're not likely
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to find a more misunderstood character in any other cartoon series. Raven constantly struggles between her deeply instilled habits and her want for friends. Although some of the Titans like Robin and Starfire seem to "get" her more than others, her relationship with them still remains rocky due to her detached nature. Raven must constantly keep in control of her powers or else they will rage out of control with the slightest emotion.
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For the finale, I'll stick with a classic character, Lydia from "Beetlejuice." This one girl is the only contact and potential friend the trickster Beetlejuice has in the world of the living. It's just as well for Lydia too since her parents don't even really understand her, much less her peers at her prestigious all-girls school. Much like Sam, she finds herself on the receiving end of ridicule thanks to the most popular girl in school. Normally, a session with Beetlejuice and all his mischief is enough to set things straight and get Lydia into a better mood.