Oh cool, Pup discussion! I like Pup, there's so much interesting stuff going on with that character. I hope it's okay if I dump some of my thoughts about Pup too.
The things I noticed the most about Pup are
1) unhealthy perception of masculinity/feminity and obsession with trying to be like Ivan and
2) the pain and wasted potential that comes from trying to live up to an ideal that he* KNOWS he can never live up to.
*(I'm mostly focused on Act One for now, so I'll stick to "he" while that still applies because I feel it underlines the point I want to make very well)
For the first, an example that really stuck out to me was a scene where Pup tried to question/mock Cainan for his long hair, to which he calmy replied that he has no such insecurities, so those words do nothing. Cainan does not think of himself as being less manly in any way because of his hair, while Pup by contrast is stuck with a very rigid view of masculinity that does not allow for any such deviation from the norm. Similar deal with Pup trying to mock Jude (who even comes with a unisex name!) for being a "pretty boy".
For my second point, Pup's pain and self-denial is pretty much written all over Act One and in his interactions with other characters right from the first chapter. The way he pushes himself past his own limits when around Ivan, the way he rejects Satia's attention, pretty much the only "person" he seems to be okay with appearing "unmanly" to seems to be Jakson, whom Pup does allow to play a protector role for him.
So that's what I thought the curse was targeting, and what Kara was trying to point out to him. Not just that Pup sees feminity or women as weak, but that he sees feminity (or lack of masculinity) specifically as HIS weakness. The curse is extremely personal, after all! Pup has this ideal of manliness in his head that he believes he should live up even though he knows he doesn't fit that image at all, and its that insecurity which the curse exaggerates, pushing him even further away from the image he already knows he can't ever achieve. Because Pup continues trying to be something he isn't, the curse keeps being fueled.
Further into the story we also get various little scenes hinting that there are all kinds of skills that Pup apparently COULD be good at. Potential for using magic gets pointed out a few times, that he could have been a good dancer gets pointed out in ch.7, potential for public speaking in one of the support scenes with Charlotte... and of course the most important one by far which gets pointed out in every chapter; that Pup is FREAKING ADORABLE. So the point, I think, is that there is an entire world out there filled with paths that Pup could be walking and be very happy with, but instead Pup is hyper-focused on trying to walk the same path as Ivan, resulting in misery.
So in short, what I've taken away from Pup's story so far is more about Pup needing to stop denying their own self by clinging to one specific and strictly defined masculine ideal and to instead start defining their own self, regardless of whether that happens to be more masculine or more feminine. Pup is after all surrounded by characters of both genders that aren't restricted to just one end of that scale.
That's just how I read the story of course. All good stories leave a bit of room for the reader to make their own interpretations and my interpretation is probably more of a reflection of my own personal views than anything else, but I still wanted to share them after seeing this being discussed.