2 articles about Koro-sensei
The subject by its numbers · The Structure
Filed under 4. The Structure takes a structure, and this section is frames one.
Four is builder & organizer — structure, labour, and the building of lasting systems. The reference files it as a structure. Read that way, what the section is really recording is the 4's insistence that what lasts must be built patiently.
The Structure — schedules, formats, volumes, and the frames that hold everything up →Part 299: The Builder Who Taught Them to Kill Him: Assassination Classroom and the Number of Patient Work
Part 67: When School's Out for Numerology: The Vibrations of Anime's Class Clowns and Revolutionaries