I'm honestly glad to hear that, cause not everyone wants to see reason on this topic.
Well, the way I look at these things in harem games is: there's the main harem and there are miscellaneous relationships of all kinds. The main harem is the central group of characters that may or may not have a deeply emotional and romantic connection to the MC. They may or may not also live with him after some point in the story. Suzu is the obvious example for this.
However, that doesn't mean that characters outside of the harem won't get any romance or romantic relationships with the MC. It's less likely but there's still the chance for a separate (from the harem) relationship with individual characters. Miri would be a good example for that. There's gonna be more than just a sexual relationship but (as of right now; things might change during the development) she's not gonna move in with MC and become part of the core harem.
I hope this sufficiently explains things without spoilering too much. :)