Mmm, well, the flirty moments that stand out to me are if the fem!PC talks about boxing (which inspires Chris to fish for a compliment), and when you talk about Mia (where the PC gets to add her own thoughts on Mia's breasts after Chris comments). Without either of those (and I think you may have to respond in a way that makes her think you're interested in order to get the points, now that I think about it) I don't think fem!PC has the affection points to get invited to drinks - I don't think the other conversation options have an influence on affection either way (except to tick her off by criticizing her crew).
Incidentally, the lead in to either of those doesn't strike me as especially flirty from the PC's end - it's just making casual conversation, really, talking about her hobby and talking about a magazine lying around. The PC opens the door admittedly, but Chris is the one who takes it there.
I think it's pretty much the same as with m!PC, actually - it's just that in his case, his only option is to do the boxing, with the magazine just being an interesting story.