Maple! She's been my fave since Wild World. She followed me to City Folk and then New Leaf as one of my starters and now I don't want a town without her.
Definitely Maple! Though Judy is a close second.
I had Maple in Wild World, and she randomly moved out without saying a word and I was totally heaaaartbroken.
Pekoe. I remember I used to hate her so much as a random villager in City Folk, but then she grew on me a whole lot after interacting with her some times.