Azumi Azuma is the elderly Head Priestess and owner of Tenkai Shrine, an ancient temple near Kamaya City's ocean side. Explicitly over 70 years old, she defies expectations with a youthful, playful demeanor and insists everyone address her as "Azu-chin." She actively maintains shrine operations, including tourist amenities like hot springs and overnight stays, while continuing her priestess duties.

Azumi harbors a fondness for modern teenage culture and openly admires attractive men, particularly displaying romantic interest in Cariot, a much younger clergyman from the Vatican's Anti-Creed of Fatima. This infatuation sparks frequent jealousy when other women interact with him. Her behavior often leans childlike and mischievous, though she shifts instantly to seriousness when needed.

Possessing authentic spiritual expertise, she aids younger exorcists like Matoi Sumeragi and Yuma Kusanagi against supernatural threats. She shares a longstanding friendship with the rival Kusanagi family of Tenman Shrine and comprehends the conflicts involving higher-dimensional beings and evil spirits, offering guidance through exorcism knowledge and shrine traditions. Tenkai Shrine is rumored as the meeting place of Matoi’s parents, Shingo and Shiori Sumeragi.

Azumi’s appearance features gray hair styled in buns or updos with ribbon accessories, and she is frequently illustrated with closed eyes. Her role and traits remain consistent across all documented media, cementing her as a reliable yet unconventional blend of lightheartedness and competence within the spiritual community.