We start off with Carl as a cheater (twice!) and throughout the first part of the game he seems to be an insufferable douche. All of this is perfect setup for the Submissive Path, because we get to enjoy Carl getting his just desserts. I'm not sure what part Carl would play in the larger Succubus vs Vampire story, though, as a sissified slave to Danni. (Who, by the way, needs the <futa/trans> tag and not the <trap> tag. She's definitely a trans character that identifies as female, and not a femboy dressed in girly clothing.)
For the Dominant Path, will we be able to redeem Carl through our choices to set him up as a protector for Gwen, much like Jeoffrey is for the Lady of the Castle? The pieces are there, with both of the women Carl cheated with either working for or actually being Succubi, so on the Dom path it could easily be revealed that Carl was manipulated into cheating. This leaves the door open for Gwen to forgive him and for Carl to have a central role in the coming fight. On the Dom path, instead of feeding from Victoria, maybe he can feed from Jeoffrey and transform into a more masculine form, instead of the feminine form he'll get from suckling Succubus titties.
It's an interesting story and I'm looking forward to seeing where it goes!
BTW, if there's plans to reveal that Devlin (being Gwen's father) had sex with her to create offspring (as it seemed to be inferred during the dungeon scenes) then you'll need to rewrite his relationship to Gwen for Patreon (if you go that route) and hopefully do an "unofficial" patch to add that relationship back in.
EDIT to add one small gripe: Why did Danni all of a sudden look much more masculine in the face after the reveal? Was it just the hair? If so, please consider changing it back because I liked the fact that she was a pretty trans Succubus (Incubus?). That was something new and interesting.