Bored Billionaire decides to create a social experiment by building 2 small towns where all the housing and utilities are free... but with one small catch.
Past a certain age the towns are gender-limited free-use!
In one town, males above a certain are not allowed to refuse any female's sexual advances. And in the other town, it is reversed - females above a certain age are not allowed to refuse any male's sexual advances.
Optional 3rd town where it is reward-based free-use. Residents earn reward certificates that they can use to free-use any other other resident.