The "Shrine Maiden of Hakurei" is both the facility for maintaining Gensoukyou,

and the strongest existence, responsible for the absolute elimination of threats to Gensoukyou; however,

and the strongest existence, responsible for the absolute elimination of threats to Gensoukyou; however,

The sages, who are the managers, would not allow anything to be beyond their control.

The sages, who are the managers, would not allow anything to be beyond their control.

at the same time, there must be a way of controlling her.

But then,

neither the shrine maiden nor the sages wish for a precious life to be returned to nothingness.

Consequently, in order to prevent that from happening, the shrine maiden of Hakurei lives alone in the shrine, isolated from the physical world.

She is forced to treat humans and youkai equally.

She is to receive all beings equally, but is not allowed to have deep relations with any being.

She is to receive all beings equally, but is not allowed to have deep relations with any being.

She is a bird locked up in an immaterial cage...