Akashic Records of Bastard Magic Instructor(2017)

The story takes place in a witch school; Where "Glen" teaches as a part-time teacher and forces students to study and self-study. One day, one of the students named "Sistine" gets angry with Glenn and invites him to a duel! But this invitation coincides with an incident that threatens the school, and in the meantime, Glenn tries hard to protect his students and changes the course.