John is a man who likes his girls young, around 18 to 20, just the right age for it to not be considered illegal. Because of his particular taste in women, he doesn't find his wife attractive anymore even though she is exceptional-looking for her age.
With his recent introduction to Amon and seeing his bold ways, John finally built up the courage to pursue young women behind his wife's back.
But this action of his has put him in a lot of trouble. His newfound excitement of having an affair with a young woman has made it hard for him to maintain his personal life.
He cannot allow his wife to find out about his cheating because he, too, has put a lot of effort and work into building his wealth, just like Stewart. A divorce under the pretext of cheating will ruin his life.
So when he sees Amon switching women like clothes, he can't help but be in awe of this man, and he is especially impressed by the girl Amon has with him today.
