1/3
2 Years of Service
It might be hard for a lot of cultures to understand harems, but historically harems existed for a long time. Strongest males get the most women kind of thing. What keeps/kept the women there? Probably safety and security, although many harems existed under the threat of harm too.I am honestly tired of how many games just have all the women be fine with banging each other and only the MC as if that's totally normal. Fantasy, yes I get it, but there's got to be a talented enough writer to make a reason why this would be okay with them. Mind control, drugs, money, something.
In the cases of a harem built by threats, I don't see the women being too enthusiastic, but maybe.
I don't know if this qualifies as harem exactly, but Genghis Khan is an ancestor of a huge number of people alive today.