Aether is the Greek deity of space, heaven, and the upper sky/atmosphere. He is the god of pure air, which only the gods breathe, and is not the same as Aer, the normal air that we lowly mortals breathe. Aether is a primordial deity, in existence before Zeus and the Olympians were born.
Aether isn’t really said to have an anthropomorphic body the way many of the other gods do. So he doesn’t really have attributes. He’s more like a disembodied spirit, very different from the Greek gods many people know.
Aether doesn’t really have many myths. According to Hesiod, Aether is the son of Erebus and Nyx. Another source says Chaos is Aether’s parent. His sister is Hemera (goddess of daytime). He was said to have various children, among which were Ouranos and Gaea, yet other sources say his only child was Ouranos. Aergia, goddess of sloth and laziness, is the daughter of Aether and Gaea. Aether is not said to have a wife or other partner.
Aether is the defensive wall of Zeus when he fights against the Titans. Aether is also said to be the wall surrounding Tartarus. According to the Orphic hymns, Aether is the source from which all life emanates. Aether is the soul of the world.
Light and Dark Sides
With so little information about Aether, it’s harder to tell what his personality is like. As the god of pure air and the supposed soul of the world from which all life springs, he seems like a fairly nice deity. I think primarily he should be considered a deity about purity and life. But not necessarily human life. At the heights of the atmosphere which we now call aether, we can’t breathe because there isn’t enough oxygen. Aether isn’t necessarily the god of human life, but the god of godly life, if that makes sense. In the Greek system, life came from the gods, the gods came from other gods, and all the gods came from primordial deities of the universe necessary for any kind of life at all. Aether is from that class of primordial deities necessary for any life. From what little we know of him, we can’t really say if he has a Dark side or a Grey side.