This obviously requires far more research than I’m doing, but sadly I don’t have the time or resources to do it right now. For the time being, I’ll stick to what I have.
This is just a speculation of course.
Crowley referred to his and Naomi’s good times together in Mesopotamia. This ia a nice clue, I know where to look at. He also gave a certain implication as for the nature of their relationship. That’s even better, I know what to look at.
So, after taking a nice swing in the direction of Mesopotamian deities, I came up with this:
Inanna - the goddess of war and ferility, the most influent female deity in Mesopotamia.
Etymology of her name: it is a derivate from Summerian nin-anna, which stands for Queen of Heaven.
She was associated with the planet Venus and in the mythology, she was as the only deity - able to descend to the underworld to heaven (because Venus makes a similiar descent: sets in the West and then returns back to the East): to connect that with Supernatural - even thought it was considered impossible, Naomi was somehow able to reach Purgatory and get Castiel out.
The goddess was also associated with the pisces constellation. And coincidentally, later in time fish happened to be a symbol of the Christian mythology, so perhaps the connection between her times in Mesopotamia and running Heaven right now lies somewhere in here.
Inanna was said to be treating her lovers rather unwell. Her consort was Dumuzid the Shepherd.
With this, I believe, we might be reaching Crowley.
Dumuzid was a predynastic King that ruled in Uruk for 36000 years.
The mythology differs in details, but there is one constant part to all of it: due to Inanna’s descend to underworld, Dumuzid in exchange for her, is seized by Demons and taken to the underworld. Later in poetry he seems to be a deity of some sort, the precursor of the god Tammuz.
Looking into that Crowley and Naomi’s small talk, it would fit. It is kind of implied that she was the one who left him and now wants to cut away completely from that infamous past? And we do not know how exactly Crowley found himself among all those demons.
Yet, he became the King of hell, which in a way, makes him a deity down there, doesn’t it?