This COULD be a trait, but I'm not sure I support it... I think the number of available customers is already way too high. Profits are way too easy to come by as it is.
I believe, profit, high slavery taxes and economy model will be fixed and balanced in future. And the trait slut is different from Nymphomaniac.
Ever seen Taken? Well, operations like that exist in human trafficking...
Yep... Also, Matrioshki or Matroesjka's (2 parts, 10 episodes, 2005), Human Trafficking (2005)... Taken is pretty optimistic thematic movie.
"operations like that" exists to broke girl will, who kidnapped from streets or taken from family. Clients always pays full prise and didn't even now, that he is №15 in girl list during current day. Clients didn't now that the girl is cumdump (condoms preserve them). It's IRL exp. In my country called... like "put girl in rotate"
But there is jap's way to see it, like using girls for free, and cum inside her limitless times:
http://gelbooru.com/index.php?page=post&s=list&tags=cumdumpAnd there is manga series of [Mayonnaise] about potty girls.
Since this fantasy world, better use second version of cumdump term

It's more whorish and sexy.
But first way could be implemented in list of "how to break girl without magic" ))
Add goons Job - [Escort Service]. They'll spend their time to watch girls who goes to clients. This job allows at least 7 girls from DUNGEON work as whore or cumdump.
2 goons for every rebell in dungeon. IRL way to beak girls, as described before.
Special drugs and 10+ clients per shift will increase her constitution, decrease rebelliousness, and allow to train girl properly without tortures and masochist trait.
"More clients" - classical way to obedient future ))