I don't really get the point of Brooke as a character in this story... she seems sort of the wrong shape for each hole she's been put in, she doesn't fit in an incest story, she kind of fits in an office romance role but then Mira works far better for that, her relationship develops way too fast and the fwb's path doesn't really work that differently, she just comes across as NTR bait, but i don't really get the appeal of romancing someone with the express intention being to cuck them... things with Mira make much more sense, the MC's known her a lot longer, she has reason to want him, to be jealous of him, to be thirsty for his attention but instead we get Brooke... but we still get Mira too... bit redundant no?
I dunno, she's a nice girl but for me she suffers from the same issues Vanessa does... they could be removed from the story and with just a few small tweaks everything would run smoothly and make more sense, narratively speaking.