Gyokuken Gakuganji is a supporting character in the anime and manga series Jujutsu Kaisen. He serves as the principal of the Kyoto Jujutsu High and is a powerful jujutsu sorcerer known for his strict adherence to tradition. Gakuganji is characterized by his stern demeanor, elderly appearance, and unconventional use of a guitar as a weapon. He plays a significant role in overseeing the students, maintaining order within the jujutsu community, and making critical decisions about cursed spirits and sorcerers.