Yasutaka Tsutsui (born 1934) is a Japanese novelist and science fiction writer from Osaka. He began his literary career after founding the science fiction magazine "NULL" in 1960 and gaining the attention of mystery writer Edogawa Rampo. Starting with science fiction, Tsutsui developed a distinctive body of work incorporating satire, black humor, metafiction, and experiments with language and narrative form. He received the Izumi Kyoka Prize for Literature for "Kyojintachi," the Tanizaki Prize for "Yume no Kizaka Bunki-ten," and the Nihon SF Taisho Award for "Asa no Gaspard." Works such as "The Girl Who Leapt Through Time" and "Paprika" have also become widely known through film and television adaptations. In "Zanzo ni Kuchibeni o," one Japanese kana character after another disappears from the world, forcing the novel itself to continue with an ever-shrinking vocabulary and turning the disappearance of language into the structure of the story.