I think I found the law my friend referred to that covered porn and prostitution.
This law is not just limited to C but to all human beings.
See § 4.1
Commercial sexual exploitation means profit-bringing activity, which results in the increase of the assets of the perpetrator or of other persons, expressed in the use of the victim, through constraint to engage in prostitution or in the pornographic industry.
http://www.hsph.harvard.edu/populati...va.traf.04.htm