Duncan Quagmire is a character from the book series "A Series of Unfortunate Events" by Lemony Snicket. He is one of the three Quagmire triplets, along with his sister Isadora and brother Quigley. 
He is intelligent, kind, and curious, and he enjoys reading and solving puzzles. He is also an excellent cook and often helps his siblings with their inventions. 
After the fire that destroys their home, Duncan and Isadora are separated from their brother and parents, who have perished in a fire.