It seems like a lot of the Shinigami when they were young and not Shinigami yet were a lot kinder people that were more carefree. Then something happened and that all changed for them. Though not everyone was a child when they entered the spirit world. I really cannot imagine Kenpachi as a child. And even if he had been at some point, I would still think that he would be that freakish brute of a child that you just stirred away by your first glance.

Though I guess it also depends on where you are in the whole system of the Rukongai. Kenpachi was way in the back where the criminals and life and death was everything. So it is only natural he is going to be a brute.

So are the Noble Families explained some? I know that they generally invite people into their families. Since it is rare to find someone related to you in the Soul Society. So those that are noblity are not really noble blood, just special enough to get invited right? They are all Shinigami, there is not some of them that are in the family, but not Shinigami? I guess if you were born into the family, like we were talking about before it could be possible. Though they probably would inherit their powers and become a Shinigami anyway.

But someone had to have decided on making the family noble to begin with. It seems like everything in the Soul Society was created by like one person. So his friends or whatever became the Noble and different group? Is it all favoritism and things like that? I don't know, that may not have been explained yet so you might not know.