No Longer Human is told in the form of notebooks left by one Ōba Yōzō (大庭葉蔵), a troubled man incapable of revealing his true self to others, and who, instead, maintains a facade of hollow jocularity.

In this version, Yōzō meets Osamu Dazai himself during an asylum recovery, thus giving him permission to tell his story in his next book.

[9] Leroy Douresseaux from Comic Book Bin also praised the series as tragic and delicate, while being grotesque and cruel at the same time.

[12] Derik Badman from The Comics Journal was more critical of the book, stating that Ito's art is "decent" but can feel stiff and simple in later parts.

Badman also felt the adaptation changed too much of the original novel and relied too heavily on misogynistic representations of female characters and over-used horror comic tropes.