Board Thread:Jobs Board/@comment-6697950-20130531133629/@comment-8214296-20140508052903

Cardinal said there were 'a few hundred thousand' inhabitants of Underworld.

I found how Human Unit I.D.s are possibly made. Kirito's ID is NND7:6355 and Eugeo's ID is NDD7:6361.

During their converstion with Deusolbert, he said he used to oversee the Northen Norlangarth Seventh Remote Region. NND7 is most likely Northen Norlangarth District 7.

for the number, it's most likely the number of people born in that certain region when Eugeo and Kirito were born. There are a few hundred villlagers in Rulid so the number shouldn't be too big... considering 7+ generations has passed.