Jiruo

Jiruo (by his students called Leader) is a moon whistle Delver who serves as a teacher for apprentice delvers from the Belchero Orphanage in the town of Orth. While he works as an instructor for the children, he's also largely responsible for their upbringing and well-being.

He was the disciple of the legendary white whistle Lyza "The Annihilator", and she later entrusted him with the safety of her daughter, Riko, following her miraculous birth.

Appearance
White hair with bright blue eyes, average height.

Personality
As a teacher, he cares all the students of Belchero Orphanage, ensuring the safety of all including bell-bearers, however, he is strict during night time patrols.

History
When he was at young age, he had already been a red whistle delver; he received from Lyza the duty to take care of her child, Riko. In Lyza's conversation with Ozen, Lyza said that she expected him to hide Riko's identity before her Last Dive into the Abyss.