Encourage her to become an even bigger whore, then convince her she might as well get paid for her whoring.
Get her into only fans/porn and pocket the money from her whoring.
I'd start her up on a drug/coke habit too to further facilitate her whoring and my profiteering.
(In reality though I'd never let myself get into a situation like this guy and I'd be too lazy to bother with the above as there are far easier ways to make money)