It was mostly to point out that these women will 'fuck' each other too, the MC being there or not, and that in a polyamorous relationship (like a throuple), they all love each other, the MC isn't central in that, he's part of that. That's where most people mix that with 'harem', and cries 'NTR' when they realize it isn't. Best depictions of that in the AVN world so far, to me, would be the Josy/Maya throuple in Being a DIK, and the possible, multiple-partners polyamory relationship in Bare Witness.
And as of right now, there's no 'harem' intended for Artemis. (fortunately)
I have to say, I understand your precision, and yes, both aren't mutually exclusive, I say 'polyamorous relationship' because I dislike the word 'throuple', my first language is french and it reminds me of 'troupeau', which is 'herd' in english, so yeah