The school principal who initially punishes Dash with a disciplinary mark. He confesses to forging the auditorium's safety inspection report, which caused the disaster. To save the survivors, he sacrifices himself to leverage open the bleachers, allowing the group to reach the roof.
Grimm exercises institutional authority over Dash and directly escalates their conflict.
Principal Grimm puts a mark on Dash's permanent record after Dash writes a hurtful article about Assaf.
Grimm represents the school authority whose failure endangers Mary and the other students.
As principal, Grimm oversees the school while Mary is a student navigating the disaster caused by the unsafe auditorium.