Montressor is a sadistic character and the main antagonist in Edgar Allen Poe's short story The Cask of Amontillado.
There is not much known about Montressor's past. One could tell that he was brought up with much money due to his tremendous wealth. He also mentions that he had a great and numerous family to Fortunato once inside the catacombs.
One night during Carnival Season Montressor approaches who he calls his friend Fortunato with intentions to trick him for insulting Montressor some time prior to the events of The Cask of Amontillado. He approaches a drunk Fortunato and tells him about a rare type of wine Montressor supposedley bought for a high price. Eager to see it Fortunato immediatley wants to go to Montressor's vaults and try some. Montressor pretends to care about a cough Fortunato had discouraging him not to go. Fortunato does not listen and goes little did he know thats what Montressor wanted all along. Once to the deep underground catacombs Montressor leads him to a near by cave and chains Fortunato the wall and starts to build a brick wall in front of him to trap Fortunato laughing sadistically teasing Fortunato. Fortunato begins to scream, sobering up but this is all to no avail. Montressor mocks Fortunato as he imprisons him.
Fortunato then pleads mercy. Montressor feels remorse but this does not last as he places the final brick into the wall. His remorse then returns after and cries out Fortunato's name, worried, but there is no answer. Montressor then says that no one has found out about the murdering for 50 years.
Throughout the story Montressor proves to be highly arrogant possibly suffering NPD (Narcissitic Personality Disorder). He is also shown to lie occasionally and seems to be good at it. It is also possible that he has murdered more people due to the skeletons in his catacombs.