Referred to as the 'Bastard Magic Instructor' (BMI). Initially appears lazy and incompetent, but is secretly a former Imperial Court Mage Corps assassin hiding his power due to a remorseful past and severe depression. Forced to reveal his true abilities during a school attack. Ultimately finds meaning in teaching as his students help him overcome his depression.
Glenn's entire seasonal arc is driven by his evolving responsibility toward Sistine, making her the emotional core of his journey.
Their relationship moves from direct opposition over Rumia's fate to a tense but necessary alliance during the facility breach.
Rumia's vulnerability consistently triggers Glenn's intervention, anchoring his motivations throughout the terrorist crisis.
Albert serves as a reliable partner who shares Glenn's risk, solidifying their bond through shared combat exposure.
Sistine strives to prove herself under Glenn's guidance and ultimately becomes his savior in battle.
Rumia maintains unwavering loyalty and hope for Glenn's return despite his disappearance.