Well, if we talk about the original version (which is conceived by the developer), then yes, there is no harem path. In the end you have to choose who to stay with. Also, the developer in version 0.37 added a new branch, which branch I do not know. I did not go through. But on the first page There is a mod that adds the harem path, again, I have not played with this mod, and I have no idea what's what and what the mod adds. There are questions to the creator of the mod.
P.S.I still hope that there is a kind person who will share the saves for the game. And I advise you to start with New Game +, make your life easier, and spend less time. Because of this, I don’t want to replay, there’s not so much time to start everything from scratch. But so far there are no good people. Alas and ahh.