Okay Fellow Readers im goin to speculate here but what if Asa is hiding the greatest secret in this entire series think about it everyone we only know his first name Asa and dont forget the yozakura family name started with tsubomi in other words what if Asa's true full name is really Asa Asano and the only reason Tsubomi's was changed was because of her genetic mutation she was born with meaning taiyo is the key to making their bloodline stronger dont forget my fellow readers not just anyone can be compatible with Tsubomi's blood since she was the first yozakura founder and its first family head I think my fellow readers that the reason they dropped their original family name and started a new one was because back then they were treated as freaks of nature or monsters if u know how stuff like tht goes so yea thats what im speculating so far and dont forget we know almost next to nothing about Taiyo's ancestery dont u agree my fellow readers? 
