Continued.
He could just take that, to avoid the awkwardness - haha just kidding Keltham is an Abadar cleric.He could say he'll only take one silver and proceed, but then he'd feel bad about not being sure it was actually worth even one silver to her, and Keltham does have any ability to notice when he's about to perform a sex act he'll feel bad about.
"Yaisa, ten silver is half of your daily salary, that's really high as a true value on one sub-act of sex where we do things slightly differently for a couple of dozen minutes. An actual transfer of five silver was what you named under Fairness for a whole day masturbating without coming -"