So I'm guessing all the kidnapped women get brainwashed automatically by whatever that exists in that world...
Apart from the kidnapping, the brainwashing(?), I think the lack of 'oh shit wtf is wrong with this world?? how do I go back?? my family?? my previous life??' makes it all seem like the author just wants a super convenient setting for the reverse harem.
If you can give zero shit to all that, it could be enjoyable, more or less. (Which is what I'm doing to enjoy the story(?) so far...lol)