Better quality http://www.jabarchives.com/main/post/Z9EQ5L4147369735125516122231
Col. Calloway and Miss Grimwood have fleshed out backgrounds but their basic personalities aren't TOO dissimilar from the original movie so I won't go into it much, just to say that they'd both be a little less goofy to match the tone of the reboot.
"Nocturna" is a mashup of horror hosts (like Vampira, Elvira, Svengoolie, ect.) that Sibella fixated on at an early age as a proxy mother figure, lacking a proper female role model in Castle Dracula. Her sultry stage voice is the basis for Sibella's own husky affectation of an American accent, despite being raised in Romania. In the episode "The Star", Sibella meets her idol in person at a horror con, finding her a pale shadow of the 80's late night icon that she knew. This shakes Sibella, but by the end of the episode her faith is restored and she learns to separate the person from the legend and becomes a little more mature.
Mothgirl is sort of a bully character, who has a chip on her shoulder against Sibella specifically. I swear I'm not trying to focus on Sibella stories exclusively, it just happened that these two were next to each other in my notes. Mothgirl is motivated out of jealousy for how easily (from her POV) Sibella is able to integrate into human company and engage with human males in particular, since Mothgirl is rather thirsty for some close contact. So when Sibella starts taking flying lessons (in her tiny bat form) Mothgirl takes it as a personal invasion of her "turf" and sets out to harass and intimidate the poor little purple bat. Eventually the two do reach an understanding and make amends, with Sibella offering to teach Mothgirl how to approach a boy without terrifying him. Around the same time as this personality shift, Mothgirl undergoes a molt to outwardly reflect her new lighter disposition.