Making Fiends/WMG

Clamburg is in Massachusetts!
Okay, I'm sorry for all the crazy, crazy theories I've been posting here lately, but I swear, this one might actually be true. All these subtle hints! It's as if Amy Winfrey was just waiting for us to put the pieces together! Exactly as planned!
 * Clamburg is a costal town that is implied to be close to Canada.
 * Malachi is explicitly stated to be a Puritan on his Nickelodeon page bio; Massachusetts was originally settled by Puritans.
 * One of the chief seafood exports from Massachusetts is clams.
 * Finally, Massachusetts borders Vermont, Charlotte's home state.

Every Secondary Character Will Get an Episode Dedicated to them

 * Think about it, Marion, Marvin and Mr Milk all got an episode specificly about them such as new best friend, Marvin the middle manager and Toupee! so it's not that far a strech to believe that Maggie, Malachai and Mort would get their own episodes.

Making Fiends is an alternate universe version of 1984
Vendetta is Big Brother and her Fiends are the Thought Police. Clamburg is Oceania, and the surrounding towns of Molding and Tinspit are Eurasia and Eastasia. The students and staff at the elementary school are members of the Inner Party, and the rest of the townspeople are the Outer Party. Singing and expressions of happiness are considered Thought Crime. Because Clamburg is such a small town with so few people, Vendetta can walk around Clamburg freely without having to worry about being assasinated. Mr. Milk is this universe's equivalent of Winston, which makes Mrs. Minty Julia. Charlotte is a little harder to place, but I think she fits in pretty nicely with this guy. How I come up with this crap, I do not know.

Charlotte does not exist
She is just a manifestation of Vendetta's guilty conscience. Having finally cracked from the pressure of being a young dictator, Vendetta began to hallucinate her polar opposite one day during school. At first, Mr. Milk and the students didn't see her, but Vendetta kept on insisting that there really was a stupid blue girl tormenting her, and being very afraid of disagreeing with Vendetta, they played along and after a while began seeing her too. Vendetta (and by proxy, her classmates) will eventually lose her mind to these hallucinations.

Charlotte and Vendetta both suffer from delusions
Charlotte was so frustrated her parents died, that her brain made an alternate reality, a perfect one. That's why she moved to Clamburgh, to escape. Charlenne, Charlotte's grandmother, played along with Charlotte's "game". Now, Charlotte hears what she wants to hear. Rude comments are bleeped out of her mind,and she only hears vague comments like "Go away" gently, and Vendetta's "stupid girl" comments in a warm tone. This can explain why she's so destructive. Also, Vendetta is so stressed by Charlotte that she sometimes delusions her worse then she is, as seen in the journal-diary episode.

Charlotte and Vendetta are alternate world versions of Glinda and Elphaba
Not only are they green, as in Elphaba's skin color, and blue, as in one of the many colors Glinda prefers, and that presumably Charlotte would have blond or red hair and Vendetta black, but their personalities are unusually similar. Minus the fact that Elphie never tried to murder Glinda, or hated her horribly (loathing doesn't count). Also, the Les Yay is around half as much as Gelphie.

Vendetta owns a Death Note
Grudge is her shinigami. She never uses the Death Note because she finds it more fun to terrorize the people of Clamburg with fiends. It did occur to her once that she could use it to kill Charlotte, but Charlotte is so stupid that she can't even remember her own last name. Grandma Charlene is reluctant to give out Charlotte's last name because even mentioning it brings back painful memories of the accident that claimed Charlotte's parents' lives. Vendetta doesn't want make the eye deal because she wants to rule Clamburg for a nice long time. Now all this page needs is a Doctor Who or Neon Genesis Evangelion tie-in theory, and it'll be legit.

Clamburg is purgatory, or possibly Mu.
Some general facts about Clamburg: Clamburg is the Mu to which the Death Note rules refer. Everyone in Clamburg was a Death Note user in their past lives, and must now suffer the constant torment of Charlotte, Vendetta, and the fiends. Memories of a time without Vendetta and the surrounding towns of Molding and Tinspit are false.
 * Clamburg itself is a very horrible place to live.
 * The elementary school sign has been bitten off to read "Mu Element".
 * Vendetta is abnormally intelligent and diabolical for a child her age.
 * Everyone in Clamburg is tortured regularly, even Vendetta.

Vendetta is a Symbiote.
She practically has a physical aversion to music or loud noises of any kind. The Symbiote itself could be a fiend that she lost control of at some time, resulting in it taking over her body. Since the base of a fiend seems to be the greenish dip that  in episode 20, perhaps the fiend was that given sentience through an accident during its creation? Either way, its influence now drives Vendetta to create more fiends, so they can take over the earth.

The entire series takes place in the mind of the protagonist of When I am Sad.
The two main characters represent internal conflict between the little girl's sadness and happiness. Vendetta represents her violent, gloomy sad feelings, and Charlotte represents her kinder, happier side. (Bonus points that When I am Sad was animated by Vendetta's voice actress!}

Charlotte is not actually a ball of sweet dumbness, but either a vigilante or a Super-Evil level person actively trying to make Vendetta go mad
Every action Charlotte does seems to only make Vendetta angrier: insults and death threats bounce off her like rubber, her fiends either fail miserably or fall for Charlotte when she pits them against her, and her homicide attempts fail miserably. When Charlotte took the "Are you evil" test in the beginning of the series, she was actually either answering truthfully or actively attempting to get the result most likely to drive Vendetta to fits: the "Super Evil" answer, one step of villainry above Vendetta herself.

Charlotte is an angel.
More specifically, she's Flonne tasked with a mission in the manner of Dokuro. In a possible future, Vendetta's fiends have taken over the world, so Charlotte was sent to do one of two things:


 * Turn her good through The Power of Friendship
 * Which is backfiring because Vendetta's simply too mean, resulting in all the show's hilarious chaos, and Charlotte is such a pinnacle of innocence that she doesn't understand.
 * Punish her by sticking her with a paragon of friendship she can't overcome and put her in her own personal hell
 * Meaning Charlotte is sort of a Heroic Sociopath for hire, and her cheerful facade is Obfuscating Stupidity.

Her parents aren't on a spaceship, they're in heaven. And the reason fiends react to her is because she can help redeem them, and the ones that can't be redeemed are hurt by her holy powers.

Charlotte is delusioning everything
She is so frustrated over the death of her parents that she either fell into a coma or began delusioning herself into a "perfect" world.

Vendetta is the Reincarnation of Black Mage.
And the universe still exists to torture him/her, which is why Charlotte exists.
 * Charlotte is Fighter. Tell me it doesn't fit.

Charlotte is Gigyas.
Think about it: Gigyas feels an overwhelming feeling of happiness and simply ends. The only possible remains of Gigyas would have to be a condensed form of pure, near demonic bliss...
 * This explains a lot, and maybe charlottes grandmother knows this! such as in parent's where she reassures Charlotte that her parents are in space because if she knew the truth......

Clamburg is Silent Hill.
Coastal, crapsack town infested with monsters?
 * Does that make Vendetta Alessa?

Clamburg is in the same world as Salad Fingers
It sums just as barren and surreal to fit in.

Charlotte's parents are dead
It seemed obvious. The whole "They're in space" deal seemed like an elaborate lie by her grandmother to shield Charlotte from the tragedy - or maybe Charlotte does know but they keep it a secret.

Charlotte is Finn's sister
The idea is Charlotte is a blond with blue eyes, like Finn. Both have a ton of optimism, and love puppies. Charlotte and Finn could have been separated at birth, and Finn got sent to another dimension, and Jake was Finn and Charlotte's puppy from when they were babies.

Making Fiends is in the same universe as Invader Zim
And Zim and Vendetta are going to meet eventually and scheme to destroy Dib and Charlotte.

Vendetta is Older Than They Look she looks.
Probably by 3-5 years. I say this because:
 * Her voice is deep for her supposed age.
 * She calls Charlotte a "stupid little girl", but if she's the same age as Charlotte that would make her a hypocrite.
 * While this is just a cartoon, an 8-10 year old dictator is a little odd. Especially since it seems like she's been ruling Clamburg for years.
 * She's quite intelligent...in a few ways.
 * Her personality is more reminiscent of a bratty teenager than a spoiled little girl.

My theory is that Vendetta uses artificial methods to stay thin (she can't be, as Charlotte described, "slender and fit" when all she eats is clams, beef jerky and grape punch, as well as sitting around all day crafting fiends or reading magazines) that work too well, resulting in her being malnourished and having stunted growth. And obviously, nobody will have the guts to tell her she's too old to be in grade school.