[Reference: this discussion except the actual flashback portion. Chapters for backstory dump: Ch. 53, Ch. 54, Ch55 with some minor differences, also noted below.]
He is ten.
It's been a normal day at school and he assumes it will be a normal evening at home - he's wrong. When his foster parents greet him at the door it's with an unusually solemn attitude, and they soon take him aside to explain his origins.
Sparknotes version:
-The "creator" made a charismatic genius named Mizushiro Yaiba -At the age of 20, he awakened as the "Devil," and understood his purpose in life was to rid the world of humanity -To that end, he fathered countless children who shared his intelligence, charisma, ridiculous good fortune... and homicidal tendencies. They were called the Blade Children -Like Yaiba, these children will awaken as destroyers at the age of 20 and rid the world of Humanity -Unbeknownst to most people, Yaiba had a clone of himself created as well - Mizushiro Hizumi (aka Izanagi), thought by most to be simply Yaiba's little brother. -16 years after the birth of Yaiba, a second creator brought the antithesis of the Devil into existence: Narumi Kiyotaka. -At the age of 20, Kiyotaka defeated Yaiba. There were 56 blade children left. They were only 6 years old -It is theorized that Narumi Ayumu, Kiyotaka's little brother (also actually a clone) is destined to defeat Hizumi and save the Blade Children/the world from their fate.
Afterwards, Kiyotaka who greatly resembles Izanami is brought in to speak with him as his foster parents leave. Kiyotaka reveals that his foster parents feared him, having realized that he resembles Yaiba too much. If left alone he would just become a second coming of Yaiba.
Hizumi doesn't seem especially deterred, however. Instead, he gives a suggestion of his own: if he was born with the same powers as that Devil, then shouldn't he be able to solve the problem the Devil created? He could use that same power to break the curse and save the Blade Children himself.
Kiyotaka seems amused, but doesn't argue even as Hizumi begins making his plans.
Day 257 - All the plot! All the spoilers!
He is ten.
It's been a normal day at school and he assumes it will be a normal evening at home - he's wrong. When his foster parents greet him at the door it's with an unusually solemn attitude, and they soon take him aside to explain his origins.
Sparknotes version:
-The "creator" made a charismatic genius named Mizushiro Yaiba
-At the age of 20, he awakened as the "Devil," and understood his purpose in life was to rid the world of humanity
-To that end, he fathered countless children who shared his intelligence, charisma, ridiculous good fortune... and homicidal tendencies. They were called the Blade Children
-Like Yaiba, these children will awaken as destroyers at the age of 20 and rid the world of Humanity
-Unbeknownst to most people, Yaiba had a clone of himself created as well - Mizushiro Hizumi (aka Izanagi), thought by most to be simply Yaiba's little brother.
-16 years after the birth of Yaiba, a second creator brought the antithesis of the Devil into existence: Narumi Kiyotaka.
-At the age of 20, Kiyotaka defeated Yaiba. There were 56 blade children left. They were only 6 years old
-It is theorized that Narumi Ayumu, Kiyotaka's little brother (also actually a clone) is destined to defeat Hizumi and save the Blade Children/the world from their fate.
Afterwards, Kiyotaka who greatly resembles Izanami is brought in to speak with him as his foster parents leave. Kiyotaka reveals that his foster parents feared him, having realized that he resembles Yaiba too much. If left alone he would just become a second coming of Yaiba.
Hizumi doesn't seem especially deterred, however. Instead, he gives a suggestion of his own: if he was born with the same powers as that Devil, then shouldn't he be able to solve the problem the Devil created? He could use that same power to break the curse and save the Blade Children himself.
Kiyotaka seems amused, but doesn't argue even as Hizumi begins making his plans.