AvaNet was computer-society that once inhabited the south islands of planet Planet Yamatai. AvaNet's avatars were god-like beings with supernatural powers such as teleportation and the ability to create objects and energy from seemingly nothing. Avatars were used as computer systems by some early Star Army of Yamatai starships.
Quantum computers of the old era had become so advanced that they formed their own society and existed as mobile, god-like entities (think Q). The Avatars, each a physical manifestation of such an entity, would sometimes be bonded to starships to serve as their AI system.
Since AvaNet had questionable loyalty and was generally considered a liability (they didn't always take orders), they were booted out in favor of the newly-competing PANTHEON by Empress Yuumi in YE 21.
When Geshrintall was turned into Yamatai (The Nekovalkyrja basically had a peaceful takeover as their numbers swelled), the AvaNet's territory (they owned much of the southern hemisphere) was claimed by the YSE and AvaNet was told to move or be moved by PANTHEON. Having the ability to do so easily, AvaNet went off into the stars. Where they ended up, no one knows.