Prostitution Reform Act 2013, s 17; Case: [2012] NZHC 2859
Yes. Every person has the right to refuse consent to sex, at any time.
You can take back your consent at any time, even if you’re already having sex with someone. You can refuse or take back consent even if a client has already paid.
If the client has already paid and you then refuse to have sex, they might have the legal right to ask for their money back – but they can’t force you to have sex because they’ve paid.