Sector 6 was a star sector.
Three major battles of the Intergalactic War occurred in this sector, along with many smaller engagements.
The star orbited by Terminal was in Sector 6. (C: Terminal)
It was also the location of the planet Obsidian - Obsidian had a position of key strategic importance but remained neutral. (C: Volcano)
Domo may have been in this area - it was described as being on the edge of the Sixth Quadrant. (D: Assassin)