Personally, I expect them to be completely devoid of any sense of shame or moral compass. It's simply not consistent with the personality type.it doesn't change that at all,but I don't think anyone with a functioning brain would expect these popular girls to be nuns,especially in these circumstances. I don't get why would someone be upset about that when they aren't betraying the mc since they are not together.
It is obvious though that there is no reasonable avenue to them becoming any deeper than they are. Making any of them "love interests" to the established MC would have to ignore every bit of the foundation already in the story. Porn logic can only stretch so far. Trying to do otherwise is essentially saying the reader is too stupid to notice.