That's fair. Tbh, I don't take any side girl as a serious love interest, I think they're all here just to be part of the hottest scenes in the game, and in this case, Quinn, Riona, Sarah, Melanie, Camilla, Lilly and now Bianca, they're all top tier.
I can see that there's some effort to make some of the side chicks into something more. Quinn is almost achieving the status of a main girl and is featured in most of these promotional posters alongside with the 5 main LIs (In my opinion, she is the one that should be part of the main LIs due to the amount of content that she gets alone).
Lilly, Nicole, Riona, Jade and Nora have this type of development that implies that maybe the things could escalate, but none of these strikes as a serious committal relationship possibility.