From the reader's perspective, the chief difference between Paul and the college student he meets is that, while the former is the story's protagonist and is described in some detail, the latter comes and goes in a single brief paragraph and we know very little about him. We are told that he is a "wild" boy from San Francisco and is a freshman at Yale. He is on a short visit to New York and offers to show Paul "the night side of the town." They stay out all night, returning to the hotel at 7:00am. Finally, Cather tells us:

They had started out in the confiding warmth of a champagne friendship, but their parting in the elevator was singularly cool. The freshman pulled himself together to make his train and Paul went to bed.

Since the boy is a college freshman, he is presumably slightly older than Paul. He is described as wild but, unlike Paul, seems able to keep his wildness within socially acceptable limits. The fact that he is a Yale freshman who is familiar with New York City nightlife may well mean that he is the type of wealthy, sophisticated character Paul would like (and is pretending) to be.

It is not entirely clear whether the night-long journey from confiding friendship to coolness is altogether mutual but, if Paul has not had experiences like this before, he may well be the one who is surprised that an friendship which begins instantly is likely to vanish just as quickly.

Since the Yale student is the one who offers to take Paul out (and clearly the leader and motive force behind their expedition) it is likely that he is rather less naive and more accustomed to the social dynamics of such situations than Paul. He and Paul are not two of a kind, and they have evidently discovered this by the time they part ways.