Once upon a time sounds like a good way to start this, because it was once, in an age even more ancient, than antiquity, there lived two vessels - bodies.

 

They were both little girls and born in a tribe that lived in an area, we now know as the Saharan desert. Back then it was a forest, with luscious vegetation and a large population of animals. 

The tribes worshipped the sun and the moon in unity. 

Later on, their descendants should become the Greek Titans and Pantheon, and the Egyptian Ennead.

But then they were only one tribe worshipping both deities, celestial bodies. 

They were not entirely human, but also not entirely gods, or chaosborn. 

In their inability to really differentiate between one or the other, even though some of them were long-lived, or had the potential to become immortal; they asked their rulers, their makers, for a sign -  because they wanted to know, what they were and if they lived correctly. 

And it just so happened that following this, on a blood moon, Phion was born. 

A few hours later, when the sun was at it's highest, Phite was born. 

Those children were weird, in that one of them had star patterns all over her obsidian skin, thus she was called Phion, meaning illuminated and the other had golden eyes. This was not all though, the girl named Phite had hair the colour of a lioness and Phion's eyes were silvery grey. 

Phite meant to shine, or glow.

The shamans determined, due to all of the above that these kids were the incarnation of their gods and raised them as sisters. 

However, this was not how they felt, and not what was intended by this blessing.

 

When they played together, at the start, it was with innocence and even though Phite's temperament was more energetic and Phion was more of a night person and focused on acquiring knowledge, they always got along. Kindness was an integral part of their relationship. 

Always protecting the other, while one slept. 

As they grew older, their waking and sleeping rhythms met in the middle, even though Phion still went to bed late, she didn't sleep all day any more.

In their teenage years, they started learning and each found a profession that aligned best with their gifts, while Phion became an oracle and was proficient with the dagger, poisons and other herbs; Phite became a warrior and though proficient with most weapons, she preferred the sword and trained day in and day out, when she wasn’t out on the hunt.

They were always close and oblivious eyes wanted them to marry into their families, and saw them just as sisters to each other, but the moment they bloomed into women, their eyes never strayed from one another - not even once.

No one could do anything, as they married and didn't stop living and being together - now in deeper sense than before. 

Yes, there was jealousy and bitterness, from the tribe, but this was a very sensible species and as such they never started a war, however they still parted ways. 

The tribe broke apart and some of them left, but they had tried to convince the women, to not keep their gifts to themselves and start a bloodline with the tribe - they refused. If they could not start a bloodline with each other they refused to mingle with anyone else. 

Suddenly, on one night of a new moon Phion saw that the Sahara, the paradise they had lived in, grown up, and fallen in love in, would soon turn into a desert. 

And as she shared it with the remnants of the tribe, the previous division of the tribe, which had started already, aforestated, became more grave, and made them all leave. 

This previous division had set into motion the groundwork for the genesis of the Egyptian and Greek Pantheon. 

One that worshipped the sun and one that worshipped the moon with greater emphasis, than the other, but still not entirely ignoring either one. Which might make it seem that they each still worshipped both in a way.

The women were abandoned in the now desert, as they didn't want to part from one another and become the moon/night god for the splinter group that only worshipped the moon. Or for the other to become the sun/day god of the other segment that only worshipped the sun. 

This had been their last effort to have their personified gods with them, but the women refused - again.

Now, the remnants of this tribe believed to know that the gods one worships, should never become mortal or close to it, because they never followed the expectations of a non-immortal mind. 

Some of the people, though became convinced that they could do it better and as they were not human to begin with, they finally ascended to gold or wine red-blooded deities in their own right.

Even after a long time, Phion and Phite did not join them. 

Instead, they stayed in the desert and were said to be responsible for each oasis and the underground rivers, which flowed beneath the yellow ocean of powder.

 

And then they disappeared.

Maybe their celestial bodies called them back, maybe their bodies were eventually exhausted, as these beings were not suited for that much energy. Or maybe it was because of not having a mission any more.

Whatever it was, as far as we know, this is just another secret buried beneath sand near an Acacia tree.