This◊ St. Elsewhere parody has the interpretation that Frankie Foster is autistic and that the entire series is a fantasy world she lives in.
There's also speculation that Frankie is an Imaginary Friend that Madame Foster made based on herself when she was younger, due to the fact that nearly nothing about her past or personal life is shown or revealed.
Or similarly, that Madame Foster IS Frankie, time-traveled to the past.
Since Word of God has explained Frankie's backstory on Twitter, the above theories are now officially jossed. Frankie's dad (Madame Foster's son) had a terrible relationship with Mr. Herriman, and so forbid Frankie from having an imaginary friend. When she imagined her own they were taken away. Now she lives at Foster's with her Grandma in hopes of reuniting with her old friend. This calls for a reevaluation of her relationship with Mr. Herriman:
Does Frankie have a bad relationship with Mr. Herriman due to being a Mean Boss to her a good portion of the time, does she partially blame him for why she lost her own imaginary friend (since it was him that caused her father to hate imaginary friends in the first place), or is it a mix of both?
Believe it or not, even Bendy is subject to this. Some people believe that his creator really did blame him for his own misdeeds, causing him toJump Off The Slippery Slope, because it's the only thing he really knows. This isn't entirely baseless; at the beginning, when his family's giving him up to Foster's, the kid is in the typical "I know I messed up and I'm ashamed" pose (which Frankie is quick to observe and point out to Mr. Herriman) and Bendy seems to feel genuine sadness and betrayal (assuming of course that he isn't just trying to manipulate them).
There's sufficient evidence that Bendy has a soft spot for Mac. The events of his episode take place before Mac's daily visit, and in the final episode, he signs the "Goodbye Mac" card.
Once you learn Wilt's backstory, specifically how he lost his arm, the gag in the Halloween Special where he wears a fake arm that pops off to scare kids becomes subject to this: Is he comfortable enough now about how it happened to joke about it, or is he hiding the trauma behind a joke?
Bloo is an interesting example. He is revealed to be 5 years old in one episode; on that basis, does he not know how insensitive, sadistic, and selfish his behavior and actions can be and have a right to be spoiled? It's unknown whether human and Imaginary Friend years are different from each other in the show, but it's not until near the Series Finalenote the episode "Bad Dare Day" to be exact that he graps some awareness of how selfish and exceptionally rude he can be at times.
It's been established that Mac would act like Bloo if the latter's behavior didn't showcase the negative consequences of such actions. With that in mind, Bloo's Jerkass behavior could very well be a deliberate Batman Gambit to ensure Mac doesn't become a bad person, or that he doesn't get killed.
We have no idea what Mac's family background is like. Considering that his mother is either divorced or widowed and barely around, and his older brother is a sociopath who tortures Mac many times, one can infer that maybe Mac's father was an Abusive Parent and maybe a sociopath himself who Mac's mother divorced due to his apparent behavior and that Terrence took after his father, thus becoming the Big Brother Bully to Mac he grew into. Either that or the father had passed on sometime after Mac's birth and that Terrence might have had a closer relationship to his father at such a young age, and that years without him has caused him a lot of mental trauma, as shown with his terrible case of acne, crooked teeth, and his stupidity, which probably prompted him to take his anger out on Mac, who has probably handled the loss of his father much better than Terrence has, either because he was too young to know him or that the father left or passed away just shortly after Mac's birth. In short, Terrence's bullying towards Mac might be a mask to hide his frustration over the loss of his father.
Alternatively, Terrence might also bully Mac out of jealousy due to how bright and warm-hearted he is and that the boys' mother probably doted on Mac more and started giving him more attention. Since Terrence might have taken after his father, Mac obviously took after his mother, which probably fuels more envy for Terrence towards him that he takes it out on Mac.
◊ St. Elsewhere parody has the interpretation that Frankie Foster is autistic and that the entire series is a fantasy world she lives in.
