Such a fool. He doesn't even realize I'm leading him to his death.
As Montresor and Fortunato made their way into the catacombs where the Amontillado is, Fortunato was coughing and drunk, as they go to retrieve the Amontillado Fortunato only got worse and worse.
How could I not know about someone possibly selling Amontillado?
If you insist, my dear friend. The Amontillado is just within that opening there. You may go in and grab it.
My friend, your coughing seems to be getting worse. Let us turn back for your good health.
This place shall be your grave as soon as you step foot into that opening.
I am fine. Where is this Amontillado you speak of?
Fortunato had no way of knowing but he was about to fall for Montressor's trap when he would go to retrieve the wine.
Montressor
"He! He! He! - He! He! He!- yes, the Amontillado. But is it not getting late? Will not they be awaiting us at the palazzo, the Lady Fortunato and the rest? Let us be gone."
As Montressor finishes building Fortunato's tomb he claims he feels sick and he reveals that no one has gone to see Fortunato in half a century.
No one will check on him for years. He shall die without anyone noticing.