"The World's Existence"...

I will call it so for the sake of convenience.

What if the Maker... the one who created Gensoukyou, entrusted its management to some of his agents.

What if every one of those agents has the power and authority to exist outside all the law of physics.

You're talking about Reimu?

I'm talking about the position of "The Hakurei's Shrine Maiden" as a whole.

By reincarnating to a new human once every hundred years or so, she can keep doing her works unhurriedly.

It is the stone.

Deep underground The Hakurei Shrine, there lies a stone which has the same worth as Gensoukyou itself.