Having previously visited the sex shop before she decides to go again and see if anything new was in plus she likes older men and the man here suited her fantasy.
It was easier for him to abandon his cheating wife than to confront her. Another guy who just wants to get away from the bitch and stick it to her on the way.
Jerry thinks his wife is fooling around with some guy, who sopposidly has a very large cock. It takes him awhile to find out whats going on and then he has to figure out how to deal with it.