@wilddeath tru dat.
but also, most if not all of the early day harem is made for men. with 1 emperor/king/pharaoh/shogun having many, many wives/concubine/lover.
in fact, according to dictionary, harem is :
1. (in former times) the separate part of a Muslim household reserved for wives, concubines, and female servants.
2. the women occupying a harem; the wives (or concubines) of a polygamous man.
3. a group of female animals sharing a single mate.
DEROGATORY
1. a group of women perceived as centring around a particular man.
so....... reverse-harem is the right word