Eve

Eve was the first female, created from Adam's rib by God.

History
When Bart did a stand up show he said that Adam and Eve must have been the first bookkeepers, as they invented the "loose-leaf" system.

Rod and Todd asked Ned that if Cain and Abel were Adam and Eve's only children, how did they make more babies, with their mother or with each other?

Rev. Lovejoy had said that Helen and he are as happy as Adam and Eve before Eve munched them all to Hell.

Non-canon
Eve ate fruit from the forbidden tree and as a result, was kicked out of the Garden of Eden. She was helped back in by Adam and Gary the Unicorn, who died in the process. She was then flicked out by God again, along with Adam, when he found her in the garden again. This was all in Marge's dream, in which Eve was played by Marge.