"GJ Bu Comic" by Aruya. This is the 4koma manga version of the 4koma novel series, drawn by the same illustrator for the original series. It's almost exactly like the original.
Just like the original, this manga feels very light. Most other 4koma manga has one strip on the opening page of each chapter, followed by two strips on two or more subsequent pages. This manga has only the opening pages, meaning it's pretty much one page per chapter, and about half of the density of typical 4koma. It feels short and reads very fast, especially since most chapters are taken from the original.
As a standalone manga it's probably just average, but as a compendium of the original series, it works very well, covering highlights up to volume 4 of the original. Note that it's low density as a 4koma manga, but it's still higher density than the original novel series. And even though there is already an anime series, it's still fun to see the same scenes reenacted in the style of the original artist.
For people who already read the novel series, this extra manga series is worth following. For everyone else, the anime is already reasonably perfect.
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