Isabella Fibonacci is a character of T.U.F.F. Puppies. She is friends with Kitty Katswell and is best known for being Connor's assistant. Isabella is packed with information since she grew up being the smartest kid in each of her classes.
Her last name, Fibonacci (pronounced Fi-Bun-Ach-i) is a reference to a Fibonacci number and a person named Leonardo of Pisa, who was known as Fibonacci.
Quintin Matheni has a crush on her, but she doesn't notice. Isabella has him as her enemy since he is a T.U.F.F. Agent.