Answer:
His wife Mildred
Explanation:
In Fahrenheit 451 Montag, a firefighter who burns books, becomes aware that he is the instrument of destruction. After a long talk with Favor, his old profesor, Montag is disgusted with his wife Mildred and at a party in their house openly reads a book. It is then that Mildred decides to call the firebrigade (which includes Montag) to destroy all the books found at Montag´s house.
The instrument of destruction
