So let's say he found a whore and agreed to fuck her for money. Who doesn't, but why doesn't he protect himself? No matter how many times you explain to people the dangers of unprotected sex with a casual partner, they go at it again! Personally I always have condoms with me, women often have them too if they like sex!
The housekeeper showed a lot of chutzpah and assertiveness. So it would be strange if the master let it all slide. So he wasn't rude to her either, and he indulged himself in various poses, mostly crawling.