So if its multiple women sharing a man it's a harem, but if it's A man and other women sharing a woman then it's NTR? Isn't it basically the same setup?
My understanding of the genres might just differ from yours, my understanding is that NTR is when a man steals another man's woman, not two girls kissing during a threesome.
And perhaps your right, maybe my definition of Harem is too broad and a polyamory relationship is more accurate to my game but there isn't a polyamory tag. And personally I think it's still a harem if the women have lives outside of the main character.
I added a toggle for the gay content to be respectful to the people that aren't into that sort of thing, but to add a sort of anti-sharing toggle would basically remove the entire Last Beacon dimension. Emma and Rin can love each other AND the main character equally, it's not an impossible concept and it's important to their stories. Hell they don't even know they love each other yet, that's the whole point of their character arc up to this point.
The way I have written the main character is not the type of guy to selfishly hoard women to himself as sex slaves, obviously he's dating them exclusively but he's supportive of his friend's feelings, especially if he gets to watch lesbian sex at the end of it.
Bottom line is there isn't choices in my game, so there's no underlying system to make that sort of thing avoidable and for that I apologise.