Two deities watch over a child, who's tasked with eliminating prayers and to bring their corpses to the shrine as the sacrifice.
"Why did you spare that child? Wouldn't it be easier to get rid of the intruder rather than trying to indoctrinate it?"
"Because I want to. Besides, I cursed them with immortality and took their *heart* away. I would call it the most cruel punishment I could enact to someone~!"
"... Right, children must be punished for their mishaps, or they will not learn."
"I do wonder though... Every time I see them, I feel a sense of deja vu. Especially when they express happiness. Seeing them genuinely smile..."
"?!"
"But they're half human anyway, so it's not like I *want* them to be happy. I want them to suffer for the sins of humanity. I want them to suffer for what they did to me."
The Upper deity sighed in relief. Should that Lesser deity remember who that child is, he fears that they would try to excuse all their sins under the sun. To that Upper deity, that child is responsible for Lesser deity's death - that child shouldn't HAVE existed.
"And why did you name them "Shinzou", as in organ?"
"Because that's the part I took from them. To me that child doesn't have a name. It's merely a tool to serve both me and you. And it's expendable as it goes! Even if they get crushed to a mush, I could just restore their body back to normal."
The Upper deity suspects that in their thickened veneer of hatred and sadism, lies a distorted sense of care present within them. Deep down they care for the child, but due to their insatiable animosity towards humanity and for how long they had been - they just can't remember that child that they once loved so dearly.
Now they just view it as a tool. And it may be better that way.