The Priestess

"Riko"

- I can't say for sure... but I think "Priestess" is a codename. It comes up in the fairy tales of Orth.

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

According to Srajo, the Priestess 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 Priestess and a delver, if Srajo is to be believed.

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

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

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

Personality
The Priestess is secretive and utilizes the services of Delvers such as Tepaste to supply her with information.

Early Life
250 years ago, surface time, a sealed envelope thought to have been authored by the Priestess 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.