How would describe Jimmy and Bob's personalities in "After Twenty Years?"

Jimmy is portrayed as the protagonist of the plot. He has
been shown as somebody who is torn between his affection for his friend and the call of
duty.  In a roundabout way, he has been given the subtle role of the antagonist of the
plot as well. Because the only "evil thing" of the plot, so to say, was the arrest of
the "friend" who came to visit an old pal his. Jimmy proved to be a person of mettle in
the end  who preferred duty to friend.

However, Jimmy's
actions are justified in the narrative as "Silky Bob" turned out to be a thief. But, as
"Silky Bob" too kept his promise, he too, has been shown in a positive
light, notwithstanding his profession.