Kunudon

Kunudon is the official school mascot of Kunugigaoka Junior High School, a costumed character who mainly appears in announcements for school events, such as the Autumn School Festival, in a recurring video segment called Tell Us, Kunudon!, aimed at the main campus.

He comes across as sweet and mild-mannered on the surface, but like the rest of the school, he genuinely despises Class 3-E and frequently takes passive-aggressive jabs at it. His videos regularly bring up the class's past failures right before exams, holding it up as a cautionary example for the main building's better-regarded classes.

After the second round of midterms, Kunudon is fired from his mascot position and reassigned to Class 3-E, though he keeps his role as the school mascot regardless. Notably, he's so outraged when Class 3-E is allowed to go on the Okinawa trip in episode 17 that he swears out loud right before the opening theme even starts.