OK, fair enough. I might get some of this wrong because this isn't exactly my area of expertise either but basically it just has to do with the fact that Ethan Ralph overuses the word sector. So when describing his corner of the internet, gamergate and killstream etc, he naturally referred to it as his sector. At some stage he started calling himself the "King of this sector". Other people just corrupted that to sektur which is actually somewhat convenient because otherwise sector could mean a lot of other things out of context.