This is Worst characters (data) book.

Even though these are data books, they each contain omakes, or side stories:

Book 1: Flowing Crimson Edit

The end of the book featured a one shot involving a story about Rindow High's legend, Akafuji Kousuke.

Book 2: Umehoshi Edit

This part is about the Umehoshi Brothers and their time at Suzuran.

Book 3: Graduation Edit

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