User blog comment:Hakaishin Aro/Republic of Emmeria/@comment-26517142-20160813141537/@comment-28144855-20160813143155

That was 2000 years ago, now this is kinda blurred due to modernization, yet each descendant of those Clans still posses the innate ability and is using it to better society. The monsterized ones still possess those abilities but unlike the others can only have female  Kemonomimi children. Also a Kemonomimi (NM) and Human have 75% chance of having a Kemonomimi child and only 25% chance of a Human child. It will all be added in the article.

I'm also tinking of the posibilities about th erosewood boxes being important, but that is just an idea.