A trafficker can be a third party such as a pimp, but they can also be the buyers themselves. Anyone who allows trafficking to happen can be charged with trafficking as well (giving a victim a ride, checking them into a hotel room, etc.)
Sex trafficking is just one form of commercial sexual exploitation. Commercial Sexual Exploitation (CSE) encompasses ALL forms of commercial sex and acknowledges the inherently exploitive nature of the commercial sex trade regardless of state or federal statutes on trafficking.
Sex trafficking can happen to anyone but some people are more vulnerable than others. Significant risk factors include recent migration or relocation, substance use, mental health concerns, involvement with the child welfare system, and being a runaway or homeless youth. Often, traffickers identify and leverage their victims’ vulnerabilities in order to create dependency.