Actually, I am a libertarian. Really. Right leaning, yes, but I really don't like either side of the major political split. I just dislike the Republicans a leetle less than I dislike Democrats, especially those on the far left.
I go by the axiom that your freedom to swing your arm around is inviolate--unless it reaches my nose. Prostitution does that. It hits everybody in the nose; especially the prostitute's. It hits MY nose because of the dangers his/her customers bring to others, including me, if I trust my partner and allow myself to have intercourse with him, and he forgets to tell me of his previous encounter with the germ and virus carriers they are. Never mind the immoral/unethical side of it. Just look at the sheer physical danger he has subjected himself too, and is, without thought, subjecting his other partners to.
THAT sort of permissiveness isn't what libertarianism is about. Perhaps you should read this:
Key Concepts of Libertarianism to see the sort of libertarianism I hold to; especially the "rule of law" heading. "Libertarianism is not libertinism or hedonism. It is not a claim that “people can do anything they want to, and nobody else can say anything.” Rather, libertarianism proposes a society of liberty under law, in which individuals are free to pursue their own lives so long as they respect the equal rights of others."
Prostitution is the antithesis of this idea. It does nothing BUT harm, and certainly doesn't respect the 'equal rights of others,' that is, the rights of the prostitutes who so often are forced into that life, the equal rights of the people their customers encounter after they deal with prostitutes...you know, the right to choose, knowingly and freely, to enter into sexual relationships in full understanding of what dangers they may be encountering. I pity the prostitutes who have to live that life, I empathize and am angry for, those innocents who get those STD's and emotional betrayal by having sexual encounters with the 'johns' and 'janes' who have purchased those services, and received more than they paid for. I am truly condemning of those 'johns' and 'janes' who have such incredible and casual disrespect for both sides.