Pinky the Chihuahua

Pinky is Isabella Garcia-Shapiro's pet chihuahua in Phineas and Ferb. He likes to eat everything other than dog food, but his favorite food is grilled cheese sandwiches. He once swallowed Isabella's Fireside Girl Sash. Though by outward appearance he is a mindless animal, it has been revealed that he, like Perry the Platypus, is a secret agent (specifically in Wanda's Division), and is also known as Agent P.