In Chapter 2 of the 1906 story, I Am a Cat, (full text of this and preceding chapters available here), the cat makes reference to a particular "western novel" in order to draw an analogy with his master:
“Ah, and who were the women?” enviously my master asks. At first glance my master usually looks cold and hard; but, to tell the truth, he is by no means indifferent to women. He once read in a Western novel of a man who invariably fell partially in love with practically every woman that he met. Another character in the book somewhat sarcastically observed that, as a rough calculation, that fellow fell in love with just under seven-tenths of the women he passed in the street. On reading this, my master was struck by its essential truth and remained deeply impressed. Why should a man so impressionable lead such an oysterish existence? A mere cat such as I cannot possibly understand it. Some say it is the result of a love affair that went wrong; some say it is due to his weak stomach; while others simply state that it’s because he lacks both money and audacity. Whatever the truth, it doesn’t much matter since he’s a person of insufficient importance to affect the history of his period. What is certain is that he did enquire enviously about Coldmoon’s female fiddlers.
Is there a real "Western novel" being referred to here, and if so, what is it? I'm always curious about little intertextual references like this, and it'd be a shame if it turned out to be an idea the author had made up out of whole cloth.