-History-
Five years after returning home, Sato Akira found himself stuck in the Lockdown with Atsuro and Yuzu. At first, he wanted to escape. Demons were everywhere and even though he had faint memories of interacting with demons... somewhere... it was still frightening.
It didn't help that with all the people panicking, he had a constant headache. Everywhere he turned, there were new ghosts showing up, victims who died from the demons or the crazed SDF forces or the demon tamers gone out of control.
It's a wonder he didn't go completely insane.
The options he had open near the end were to go with Yuzu's idea to escape or go with Amane's plan and become the Messiah.
Yuzu's plan was one he shot down quickly. They might save their own lives, but after all those years Yuzu should have known that he couldn't abandon people like that.
Amane's plan was the one he ended up following, not because of the idea of becoming the Messiah, but of the idea of making sure that there was the right kind of justice. She was initially hesitant to approach Akira because of the strange power she sensed deep within him (not Bel, not Abel - Mot), but Remiel reminded her that she too had a strange power slumbering deep inside of her.
The fact that Keisuke and Mari had both died might have been part of the reason he took that path, as well.
He helped Gin as much as he could, though. He liked Gin's idea of sending the demons home, though for some reason he couldn't gather enough information to make it work. After becoming King of Bel, though, he had an idea.
The battle at Roppongi Hills where he faced Naoya was difficult. He didn't want to fight the person he thought of as being like a brother for so long, but it was needed. Naoya was ranting something about how God was unfair, but never quite got to the point of letting slip the true relationship between him and Akira. After that fight, things proceeded more or less smoothly, though Akira kept turning Naoya's words over in his mind.
The King of Demons could do what he wanted. And what he wanted was the demons gone. So he ordered them back to their world, and with help from the angels, sealed it back up.
However, after that work was done, he started his primary work - being God's hand of judgment. It was not work he enjoyed - he was never really a fan of physical violence, and had initially thought that he would be in more of an advisory role - but it was work he was pushed into quickly.
Even through all of this, though, he was still never told about his true relationship to Naoya. He suspects there's something being hidden from him, and knows that he's a reincarnation of Abel - but Remiel has advised the rest of the angelic host to not let Akira know who Cain is.
Cain's judgment would eventually need to be carried out sooner or later, and Akira did not seem completely loyal to their cause. It would be a test, to see whether he would be able to do it. If so, they had their Messiah.
If not, he would be destroyed.
The time for that judgment is not yet, though. So Akira does as he's ordered, trying not to think on it too much. He isn't planning on rebelling, though he really would like to stop having to kill.
At least he's managed to negotiate some more lenient punishments for those whose crimes are not as severe.