When meeting the narrator to explain himself, Sylvio clarifies this behavior by saying that he "likes" the main character. The author then uses this meeting as a platform to reveal Sylvio's true story and nature to the reader.
In contrast to the soldiers, Sylvio's character demonstrates a large amount of depth and critical thinking. His emotions do not rule his actions, which is one of the traits that make him such an excellent shot. This is a different code of valor from those of the general soldiers and officers who share his table. It is also indicative of his superior maturity, not only in years, but also in perspective.
As for the narrator, Sylvio professes to "like" him, despite the fact that the narrator appears the least willing of all the soldiers to forgive the former's perceived cowardice. Ironically, this refusal to forgive is precisely the trait that sets him apart from his fellow soldiers, and may also be the catalyst to Sylvio's urge to explain himself to the officer. When he does, Sylvio reveals the true depth of his character, not only in terms of his reactions to the opinions of others, but also in terms of how he handles his own emotions of anger and urge for revenge.
Sylvio relates the story of his initial reactions to a rich young person who at first seeks his favor. Because the young man appears to have everything in his favor, Sylvio makes a point of alienating him, but is only further angered by the young man's nonchalant reaction to these attempts. The turning point in this relationship occurs on the day of the duel. This is where Sylvio demonstrates the depth of his character, as well as the meaning that he personally attaches to the art of revenge. Because he is able to check his emotions and his taste for immediate gratification, Sylvio is able to exact a far crueler revenge than any conventional manifestation of the art, and he uses his prowess as a shot to do this. Sylvio does not shoot the young man, although according to the rules of the duel it is his right to do so. Instead, he keeps his immediate emotion intact and critically considers the impact of shooting the young man. It would not satisfy his urge for revenge, since the young man cares very little for his life. Instead, Sylvio then decides to bide his time until the young man has matured and cultivated some meaning in his life.
The culmination of the story is revealed later, also by means of a narration. Years after saying his final good-bye to Sylvio, the first-person narrator encounters a Count and his wife. They then tell the story of the culmination of Sylvio's revenge. The marriage gives meaning to the young man's -- the Count's -- life. Hence, Sylvio can effect a greater revenge than before. And he does so with great effect. The fact that, once again, he does not kill the Count, serves as another demonstration of maturity and an indication of the value of long-term revenge to Sylvio.
Sylvio's final "revenge" then remains in the memories of the Count and Countess as a permanent blight on an otherwise perfectly happy life. To Sylvio, the look of terror on the Count's face, and the emotional impact of the shot he fired, is much better and much more long-term than a death. This is what truly sets him apart from the other characters in the story. Being somewhat older, the narrator is finally in a position to appreciate the effect of this revenge.
In conclusion, Sylvio's implied distinction in the beginning of the story culminates in the form of revenge he takes on the rich young man who finally becomes the count. He inserts himself in the memories of the Count and his wife for the rest of their lives. His purpose, to somehow injure a young man that he perceived to be too perfect and having much too easy a life, is fulfilled by providing a stain in an otherwise perfect life. In this way, Sylvio's explanation and his final actions remove the mystery for the reader, but increases the respect he might expect from those who understand the art and emotion behind the concept of…