Manaka and Mona both have trauma kid responses to the situation and I think it's probably important that their respective conversations with Kurumi and Kokoro mirror one another. We're being shown that Kurumi is a stabilizing influence on Manaka, and a lot of that comes down to the trust they've built with one another. Even just having someone to talk to afterwards kinda helped Manaka see that she's overreacted a bit and isn't able to look at Mona's situation with a clear head. It's good for her to learn she has a friend in her corner who's looking out for her, even if they disagree.
The conversation between Kokoro and Mona has the first steps of that... they're not exactly honest, but they do seem to show a level of emotional vulnerability that we haven't seen from either of them. So I think this arc is going to make us consider whether Kokoro really learned her lessons from Kurumi (like, seeing the actual person and not her idealized version of them), and whether Mona can build a genuine rapport with her instead of relying on her crutch of people-pleasing.
To pull from another Kuwabara work, Tankobu, there's a scene where the aunt connects her delinquent niece being more willing to talk about her wants and needs to having a girlfriend (tho I don't think it has to be a girlfriend, any relationship that has space for emotional vulnerability). I get the feeling this arc is intended to elaborate on the value of establishing that vulnerability. Probably a rough ride ahead but Kuwabara's secretly a softie, so...
