User blog comment:B214/High School DxD EX/@comment-31137559-20170415223307/@comment-30924344-20170416013520

Ok those where my initial thoughts.

Kurenai and Airi being the oldest means they are the most experienced, knowledgeable, and maturest to lead a peerage. Being one of the eldest means you are given trust in something important. That's basic knowledge anywhere. You only become not trusted if you act like a fool and make too many mistakes. Of course you don't need to be the oldest to be what I said, but its commonly expected of the eldest children naturally. They are not the smartest no. The smartest are Helmwidge and Robertina as their mothers are the smartest girls in the harem. They most definitely have peerages. Ex is a bratty kid and bratty kids are not mature to lead a peerage. He may have one but is not allowed to do anything with his peerage until they mature. Shiroyuki and Kurobara are timid so they aren't suitable to have their own peerages yet. Shin could have his own peerage or his own Brave Saints, or both. Zen I think gets taught by Kurenai in things so he would have his own peerage thanks to Kurenai's guiding.