In the story, the Aethereans are an interdimensional species of alien "benefactors" that come with great offerings for those who join them. In reality they are extradimensional Borgs that successfully assimilated the Iconians, a species with vast technology in the Star Trek universe. Aethereans are just a Borg culture variant that comes with a different approach when it comes to assimilation.

The conceptual and narrative goal was to create a ship that would eventually come out as Borg, but it couldn't give ANY hint of it beforehand, so a cubic ship was out of question, but what about a hypercube? That's when I decided to create the whole 4D Aetherian tech element. The Harmony is cubic-shaped, but only in 4 dimensions. What we see here is the intrusion of a 4D shape in our 3D universe.