I appreciate you keeping the possibility in your mind that Quinn could possibly maybe sort of care about another human being at least
I know it's not easy to think that, given how she's portrayed in the story, but all I'm trying to say is that she has her reasons for how she is. Could she do a lot of things, maybe most things, differently and better? For sure. Could she treat Riona better? Undoubtedly. But she has her reasons for how she is, that's all I want to open people to the possibility of. I genuinely think that people are missing out on a great character and a large part of the story by taking Quinn at face value and not delving deeper into her motivations. You're not one of those people, I know, and it's certainly reasonable to adopt the viewpoint you do on Quinn after taking everything into account. At the end of the day, I view Quinn as a sympathetic figure due to her upbringing, and I contextualize her actions on that basis. You could just as easily view Quinn as a malevolent figure and be just as correct. But I want people to look at both viewpoints on her and decide which they agree with more, not have a knee-jerk reaction to some of things she does and form a shallow view.
Anyway, with all that out of the way, let me address some of your specific points in case you're interested
As far as Quinn lying to Tommy about Riona smoking for free, I don't really buy it. Your reasoning is compelling, but Quinn has treated Tommy brutally before, and I don't see why she'd start making excuses to him. Her not wanting Tommy to corroborate the story with Riona could just as easily come from a place of caring, as Quinn doesn't want Tommy to confront Riona and is taking the business side of things solely upon herself. I also don't really buy the argument that Quinn could have simply brought up the fact that Riona contributed to the hole they're in to motivate her instead of slapping her if it were true that Riona was in fact smoking for free. We really don't know the circumstances here, it could easily be true that Riona's smoking for free contributed to the hole, but that Quinn also contributed to it in her own way and so she didn't really have the moral high-ground to bring that up as an argument.
That brings us to Quinn's 'motivational' style differences. Quinn slaps Riona but not Mona in similar situations. Now, there are a lot of things I could say here, and like you say, YMMV on them. I could make the argument, which I believe, that Quinn and Riona are almost as close as sisters, and sisters sometimes slap each other. It really does happen, and those slaps don't come from a place of malice, and they don't even come from being at a stage where only a slap would work, sometimes - between very close people, siblings and such - it's just used as a wakeup call. I'm much more likely to punch my brother if he's doing some dumb shit than I am to punch a stranger doing the same dumb shit, and the intent behind my doing so would be drastically different as well. Now, whether you subscribe to that line of reasoning really does depend on how you're contextualizing Quinn's actions. If you subscribe to what I wrote in my initial post, it makes sense why she would slap Riona - in short, to wake her up, remind her of what's at stake, and to ultimately protect her. If you don't subscribe to it, it was just a mean and unnecessary thing to do, and maybe she even regretted it and that's why she didn't do the same to Mona, but we don't know. I don't think we can fairly look at the slap in a vacuum and point to it as a sign that Quinn doesn't care about Riona though, there are plenty of reasons why she might have done that, some of them reasonable and some of them not.
The wider circumstances of Quinn's and Riona's relationship are not known. We don't know the first thing about when it started, how it started, what their specific connections are to the drugs, etc. So, like you say, it's difficult to know if Quinn has genuine affection for Riona as a person because of the situation they find themselves in. Quinn's back is up against the wall, and we only have the barest idea why, so it's really difficult to know what's reasonable and what's not, where the line is in their friendship and what would cross it. Quinn is pimping Riona out. Quinn is slapping her. Quinn is talking down to her and ignoring her. And Riona is taking it all. Does that hint at how dire the situation really is? Or is Riona just extremely submissive, or does she have a battered mindset, or is she reliant upon Quinn for her drug connections, or does she think or know that Quinn has her best interests in mind? If circumstances were different, would they even be as close as they are? No one knows that except for DPC.
The one other thing you said that I'd heavily push back on, in fairness, is that from my point of view, I don't think Quinn's first and foremost concern is herself. Again, we don't know the circumstances of Quinn and Riona's relationship, for all we know Quinn could have been protecting Riona for a long time, or she could have been abusing and ignoring her for a long time, but we don't know. From what we've seen, though, I genuinely believe that Quinn is trying to protect herself and Riona in a very harsh way because of her upbringing as I outlined in my prior post. Remember, Quinn is pimping herself out as well, you think she wants to do that? I don't think she does. I don't think she wants to pimp out her girls to older men, I think something is happening with Burke that's forcing her into that situation. And as far as we know, she's protected herself and Riona from having to do that, although I suspect Quinn has probably had to do some sexual favors for Burke or someone else in the past, but I hope I'm wrong. As near as I can tell, Quinn cares primarily about herself, yes, and Riona. I don't think Quinn would ever truly betray or hurt Riona, in fact I somehow suspect a lot of things she's doing to keep afloat is connected to protecting Riona from the fallout with the drugs and prostitution. Not to cast Quinn in too much of a benevolent light - obviously Quinn is looking out for number 1, and she does treat Riona like shit, but it's to keep both of them safe, not just herself. And that dynamic between Quinn and Riona is why I believe that Riona is going to be the target of the big 'burning house' moment of this game - everyone in-game, and out of the game, likes Riona, and Riona being hurt would completely crush Quinn and make her doubt whether what she's doing is worth it. I hope I'm wrong about that as well.
You should know better than to reply to me though bro cuz you know I can only write in essay form
