Dory (Finding Nemo)
Dory is one of the rare Pixar characters that is both unique and memorable. Dory gives some of Finding Nemo's most memorable quotes while following along with Marlin on the voyage of a lifetime, despite her episodes of short-term memory loss. Dory's struggles also help her see the world differently and solve problems that the other fish can't. Now that she has her own movie, it turns out that her short-term memory loss is a kind of superpower in and of itself.
Dory is seeking a companion, while Marlin is looking for his son. Dory's sincerity and kindness are characteristics that most people like to see in themselves and others, so it's easy to see how she endeared herself to so many fans.