No Yay: Mr. Benedict tells the children (through a riddle) that the reason Mr. Curtain keeps S.Q. around is "love".... Then Mr. Benedict implies that the reason S.Q. is so forgetful is that Mr. Curtain is brainwashing him (which would remove memories of Mr. Curtain's cruelty and reduce his inhibitions).... We eventually get a less Squick-y explanation, but the implications of a villain sexually assaulting his teenage follower earlier are still eerie. Plus, the explanation came from Reynie, not any of the adult characters, and was extrapolated from nothing more than Mr. Benedict's riddle and the brainwashing.
Toy Ship: Reynie/Sticky, Reynie/Kate, and Kate/Sticky have their fans despite everyone being platonic in canon and all of them being quite young except in the last book.
Values Resonance: Everything involving the Emergency, with a constant flood of bad news making the entire world far more anxious and unable to get along peacefully, was unnervingly fitting to the time the show was released in 2021.
Constance. She may be a little brat, but she's especially vulnerable at times, and suffers more than most, since among other things she's the only one to hear voices in her head in the first book once the power of the messages gets boosted slightly, with the worry of what will happen if they're boosted to full power.
S.Q. Pedalian could count as this too. Especially when you learn in Prisoner's Dilemma that he's the way he is because Mr. Curtain kept repeatedly brainsweeping him as a means of keeping him docile and confused.
For the TV series:
Ensemble Dark Horse: Martina, thanks to her highly sympathetic depiction in the show and popular Toy Ship with Kate.
Fanon: S.Q. getting adopted by Mr. Benedict instead and joining the Benedict family (alongside Reynie, Sticky, Kate, and Constance) is a very popular headcanon. However, the Season 1 finale shows that Curtain escaped last-minute and brought poor S.Q. with him, so for the meantime S.Q. is sadly still stuck with his awful dad.
Spoiled by the Format: Tony Hale plays both Mr. Benedict and Mr. Curtain, which is probably one major reason the promotional material made zero effort to conceal the fact that they're twin brothers.
