Well, I'll just say this regarding a particular possible multi-girl ending; I got to the Katie decision in Ep 20 and I had to stop playing for a while. I get that Katie's possessive of the MC, and she does seem entrenched in this view of monogamy, and that one night of sharing with her best friends isn't likely to change her mind completely on the subject, but the fact that even after that, when it would seem that she enjoyed it a lot no matter how much she tries to use being drunk as an excuse, she still hasn't moved an inch and is still being so stubborn is irritating to say the least.
Maybe there's still time for her to change, but she's honestly starting to feel quite psycho right now and a bit bi-polar because she keeps insisting she's not a "possessive, jealous psycho", even if they're just FWB or Neutral, but then she threatens to cut his balls off if he does anything with someone else, which does seem like something a "possessive, jealous psycho" would do. It's also kind of weird how on both those paths she's declaring herself to be his girlfriend when you would think that wouldn't be the case since there's a separate path for that.
Katie's apparent rigid immovability on this feels like a real antithesis to the concept of adult games and it is, for me at least, starting to make her feel much less appealing as a character. I'm still holding some hope that she will change and be more comfortable sharing him with her friends, but unfortunately after this episode, I'm not holding my breath on that.