‘Silky’ Bob was a criminal wanted in Chicago. Yet, he came to the appointed
place at the appointed hour to meet his friend after twenty years. What
does this tell you about him?

Silky Bob's decision to come to the appointed place to meet Jimmy Wells seems to suggest that he is a loyal friend. But as we read on further, we came to the realization that he is a proud criminal, who would not shy away from showing off his success, even starting with the policeman he just met a few minutes ago.

Explanation:

The story of "After Twenty Years by O. Henry tells the story of how a crooked and wanted criminal was arrested by his best friend. But aside from the fact that he was arrested, the friend also did a more humane thing by not arresting him personally but still telling another officer to do the deed, so as not to let a criminal let loose again.

"Silky" Bob was a wanted criminal who would obviously be careful to not get caught. But despite all these, he still came to the appointed time and place to keep his promise to Jimmy Wells, his "best chum". This may infer that he is loyal and trustworthy. But then, he also seemed to be proud of his achievement, fervently telling the officer he just met all about its purpose and success. Nobody tells their life stories to the people they just met. But he seemed more proud to show off his success, smoking a cigar and having a diamond "scarf pin" with a "handsome watch, the lids of it set with small diamonds". All of these attributes to his acquired taste.

But aside from all these descriptions, his decision to keep the promised appointment shows that he may have wanted to show off his success and also to see how his friend may have fared in his ow life during the past 20 years.  

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