: Character-themed sticky notes are available for organization and display.
: The standard Japanese paper release consists of 34 volumes published by Kodansha .
If you are looking for the series to read, it is published in several paper formats:
: High-quality A4-sized paper prints featuring traditional Japanese ink wash (Sumi-e) style artwork.
Several official merchandise items feature the characters on specific paper formats:
: Upon the release of Volume 29, the Sponichi Newspaper published four different full-page ads in various Japanese regions, which have become rare paper collectibles for fans. 3. Manga "Paper" (Shonen Magazine)
The series was originally serialized on a weekly basis in , a pulp-paper manga anthology.