Originally Posted by
Altima of the Gates
Pretty sure originally it was mainly Zouken trying to get the two together, so they became childhood friends because Zouken knew about Aoi's super babymaking trait, then Kariya found out the real reason why and left Fuyuki. He still did fuck up because it would have been good if he told her that Zouken orchestrated their friendship so he could get a baby factory for his experiements, but I think context is important. If none of them really exist in that world than honestly that saves everyone a lot of mess.