Got the same feeling of knowing the friends more, it's kind of a problem of the genre imo where to better self insert your relationship the main characters tend to be fairly bland. Ironically it lends itself well to the NTR/Sharing genre well because it makes it easier to say, "yeah I'd prefer someone else too."
Yeah, that's fair, a "blank" protagonist was partly a deliberate choice to make self-insertion easier, but I could definitely give him more characterization without losing that. And Gaby specifically probably comes across as blanker/blander than the other girls, who get a lot more distinct development through their own routes and dialogs. Good point, I'll take it into account going forward.
Also, I don't want the temptation routes to feel like an easy/obvious choice, so fleshing out Gaby's own route is probably the right way to balance that out rather than flattening the others.
Thanks for your comment !