Emma is Bumblebee Man and Lenny Leonard's ex-wife. When he accidentally destroys their house, she gets mad at him and divorces him. She has the same Mexican accent as Bumblebee Man.
Emma is also seen sitting with Bumblebee Man in the First Church of Springfield, making it possible that they have since gotten back together.
In Moonshine River, she is shown holding hands with her boyfriend in New York City. It's unknown if she currently lives in New York, or she was just on a holiday like the Simpson Family.