In addition to his work with manga he is a critic, essayist, and author of several successful non-fiction books on Japanese popular and otaku subcultures.

His doctoral dissertation is "From Mickey's format to Proposition of Atom: the origin of postwar manga methodology in wartime years and its development".

Ōtsuka gave up the notion of attending graduate school after he was told by instructor Noboru Miyata that his "ideas are too journalistic and not suited for academics".

[2] After graduation, Ōtsuka worked part-time as the editor of the magazines Ryu and Petit Apple Pie, together with manga artist Yukio Sawada.

"[4] Ōtsuka contested this popular perception, later writing that he "became somewhat angry about how judgment of [Miyazaki's] crimes kept shifting onto otaku hobbies or tastes.

In 2007, he received his PhD from Kobe Design University, with the doctoral dissertation titled "From Mickey's format to Proposition of Atom: the origin of postwar manga methodology in wartime years and its development".