Kyūsaku Yumeno was the pen name of Sugiyama Yasumichi, a Japanese author born in Fukuoka on January 4, 1889, who died in Tokyo on March 11, 1936. His pen name, which roughly translates to "a person who always dreams," reflects the surreal and psychologically complex nature of his literary work. Before becoming a writer, his life was diverse and unconventional. He was the son of a major figure in a pre-war ultranationalist organization, attended the Literature Department at Keio University but dropped out, served in the Imperial Japanese Army, worked as a farmer, became a Buddhist priest for a period, and was employed as a freelance reporter for a newspaper. These varied experiences, along with a strong interest in traditional Noh drama, deeply informed his writing, which often blends ghost stories, supernatural events, and psychological torment.

Yumeno is best known for his avant-garde and bizarre narratives, working across the genres of detective stories, science fiction, and horror. His literary career began to gain attention with the novella Ayakashi no Tsuzumi (The Spirit Drum) in 1924, but his most significant and enduring work is the novel Dogra Magra (also romanized as Dogura Magura), published in 1935. This novel, which took him over a decade to complete, is a landmark of modern Japanese avant-garde gothic literature. Its plot follows a protagonist who wakes up in a mental hospital with amnesia, unsure if he is a psychotic killer or the victim of a bizarre psychological experiment. The book is celebrated for its experimental structure, its use of an unreliable narrator, and its deep engagement with Freudian psychoanalysis, making it a precursor to modern Japanese science fiction and a key text in the country's subculture literature.

As an original creator, Yumeno's direct connection to anime and manga lies in the adaptation of his literary works. Specifically, his novel Dogra Magra was adapted into an original video animation (OVA) anime released on December 21, 2012. This 66-minute animated adaptation directly brings his most famous story to the medium of anime. Furthermore, his works have a broader significance to the industry through their thematic and stylistic influence. Scholars have identified Yumeno's writing as a foundational element for what is now considered subcultural media, including manga and anime, by establishing narrative modes concerned with marginality, madness, and authority that were later revived and embraced by subcultures in the 1960s and beyond.

Yumeno’s artistic identity is defined by several recurring themes and stylistic trademarks. His work frequently explores enclosed and sealed-off spaces, such as a solitary cell in an insane asylum or a message in a bottle, creating worlds that operate by their own rules and challenge conventional notions of normality. His narratives are often surreal, wildly imaginative, and feature first-person sustained soliloquies and epistolary forms, such as letters, which add layers of psychological depth and unreliability. Other notable works that showcase these themes include the short story Binzume jigoku (Hell in a Bottle, 1928) and Kori no hate (End of the Ice, 1933). His legacy in the industry is that of a pioneering figure whose bizarre and avant-garde literary vision has continued to find resonance in modern Japanese popular culture, including anime, long after his death from a cerebral hemorrhage in 1936.