I love the idea of the wife working out of home and doing it while the husband or other family are right there sometimes just a few feet away. Rather than a massage therapist, I'm thinking something less sensual. Maybe she's an accountant and she helps people and small business people with taxes and other related things. One client she's been seeing for years and helping to save a lot of money wants to show his gratitude, and by that point she's willing to accept it.
He offers to send more clients her way and she happily agrees and ends up running two businesses.
Ok, so how about the last client becomes her pimp, so now she's a high class call girl while the husband is often home as well.I always find the key is to make it nasty as possible