OP, I've spent years studying ancient civilizations, especially the Sumerians... you'll be on a learning curve for a while :) and it will be a wonderful curve if you can remember one thing: the Sumerians PRE-DATE the Christian era (and the Abrahamic era) by a long shot. There was no Bible or Satan or monotheistic religion so you can't read and try to understand that culture against a back-drop of the Bible story because the Bible story didn't even exist yet. You won't find Satan or Devil or God (as you understand it) in the Sumerian stories, so don't try to transpose those ideas into them.

Yes, many scholars agree that the Bible stories are re-workings of the much older, original Sumerian tales and in that re-working, polytheism was condensed into monotheism, so lots of 'personas' or characteristics or attributes of the olden gods and goddesses were amalgamated.

For all intents and purposes tho, in the Sumerian stories, Enki (EA) is pretty much considered mankind's benefactor - at every turn endeavoring to further our abilities and spiritual growth, while Enlil, his brother, is the one who sought to eradicate mankind from the planet.

Kismet