From Captain Pike, to Captain Kirk to Captain Archer a span of centuries, we see examples of green slave girls.
The Federation's own charter says:
"We the lifeforms of the United Federation of Planets determined to save succeeding generations from the scourge of war, and to reaffirm faith in the fundamental rights of sentient beings, in the dignity and worth of all lifeforms, in the equal rights of members of planetary systems large and small, and to establish conditions under which justice and respect for the obligations arising from treaties and other sources of interstellar law can be maintained, and to promote social progress and better standards of living on all worlds..."
So why does the Federation captains (et al. one would assume) tolerate, indeed partake, in the enjoyment/subjugation of said slave girls?
I don't buy the Prime Directive argument, they all broke it when they deemed it was for the greater good.