What might the narrator's "perverseness" be?

In addition to the narrator's use of alcohol and his fight
with alcoholism, Poe has his narrator describe “perverseness” in some detail. This is an
added dimension to the narrator’s motivation. A reader might point out that the word
means “to make a complete about face,” “to turn the wrong way” (per = complete, and
vertere = to turn). Readers will enjoy deciphering  the meaning of this characteristic
as applied to the narrator’s actions, because Poe does not specifically state what those
actions entail and he does not explicitly state what that perverseness is,
though a reader may conjecture that it is definitely evil or dark and terrible in
consequence.