The Priestess

"Riko"

- Maybe Shrine Maiden is a code-name? It's something that comes up in Orth fairy tales

The Shrine Maiden is a mythical figure thought to communicate with incarnations of The Abyss and warn of impending danger. Cravali and his companion Tepasté are the only individuals known to have communicated with this person. She is the presumed leader of Under Nest.

According to Srajo, the Shrine Maiden cannot move past the "the final boundary" and thus relies on followers to gather information. Hariyomari's Song is the product of a collaboration between the Shrine Maiden and a delver, if Srajo is to be believed.

Nishagora's questioning of Team Riko suggests that the Shrine Maiden is either a White Whistle herself or has one at her command.

Whether the Shrine Maiden is still alive or actions are only being taken in her name is currently unknown.

Appearance
Very little is known about the Shrine Maiden or her appearance. Their only visual representation has been in the form of a crude drawing of an individual dressed in robes.

Personality
The Shrine Maiden is secretive and utilizes the services of Delvers such as Tepasté to supply her with information.

Early Life
250 years ago, surface time, a sealed envelope thought to have been authored by the Shrine Maiden and a delver collaborator was found on the 1st Layer.

An indeterminate amount of time later, her followers on the surface were contacted via letter.

Trivia

 * Miko (巫女) is a young priestess associated with the Shinto religion.