When you dream of being in a harem, then such dream indicates the sexual desire and wishes you have that were unfulfilled. Perhaps the dream suggests you to be more tolerant to different sexual proficiencies. If you are in a harem, but not by choice, then it means you are looking for approval of your sexual desires. If you are the owner of the harem, then it means you have much power, but using it on the useless things, instead of creating something more important.
Read more about dreaming of Harem in other dream meanings interpretations.