"What's the Devil's Last Name?"

Mary recounted to me the conversation she had with Madge as she went to bed.

Mares: "Madge, we're proud of you. You've been staying in your own bed so well. First off, it makes God happy, and secondly it makes Dad and me happy."
Madge: "Why does it make God happy first?"
Mares: "Because God is the first person we make happy."
Madge: "Who is last?"
Mares: [pause] "The devil."
Madge: "What's the devil's last name?"
Mares: "He doesn't have a last name. But we don't really concentrate on him; we concentrate on God, because we want to be like Him."

Hah! Madge asked a question I have never posed or thought of. What is the devil's last name? I guess if we think of a name as a definition (identity) of sorts with a genus and a species, the devil's name would be Lucifer the [fallen] Archangel. He comes from a great family (the archangels), but definitely has made a bad name for himself. But, as Mares, proposed, let's not focus on him but on God...