The Hissho starting economic behemoth has a large glowing pink ring (in space) that follows it around.  What's the meaning or purpose of this ring?  I can't seem to find any info about it, and (at least to me) it seems to have no obvious use or purpose.

See the following screenshot, if you want to know what I'm referring to:

It's a Keii ring. It's effectively the Behemoth's sphere of influence for stuff like the +20% Industry buff, and also gives a bonus to Keii from fighting in the area.

Many thanks for your explanation.  It all makes sense now!