How do Montresors name, attire, coat of arms, and family motto establish his character?

The name,
Montresor, in French, means "my treasure." This is ironic because it is his treasure,
namely "a pipe of ... Amontillado" which he supposedly keeps in his vaults, that he
uses to lure Fortunato into his trap. One might also infer that Montresor's treasure is his
reputation, which he believes Fortunato has somehow injured. It is this perceived injury which
motivates Montresor to get his revenge against Fortunato.

Montresor describes
his family's coat of arms as, "A huge human foot d'or, in a field azure; the foot crushes a
serpent rampant whose fangs are imbedded in the heel." He clearly sees himself as the
golden foot in this image, crushing Fortunato, who is represented by the serpent. The
implication is that Montresor believes that he is the hero and Fortunato the villain. He
believes that the crime he is about to commit is justified, because Fortunato, like the snake in
the coat of arms, has tried to injure him. Furthermore, he believes that the crime he is about
to commit is necessary, as Fortunato's "fangs" are "imbedded" and thus need
to be removed.

Montresor's family motto is "Nemo me impune
lacessit," which translates as, "Nobody harms me with impunity." This suggests
that Montresor is a very proud, vengeful man. For every perceived injustice done to him, he
feels that he must respond in kind. This motto, in combination with the family crest, is the
justification he uses for the cruel crime he commits against Fortunato.