In Japanese culture, oni are ubiquitous supernatural creatures who play important roles in literature, lore, and folk belief. Characteristically ambiguous, they have been great and small, mischievous and dangerous, and ugly and beautiful over their long history. Here, author Noriko Reider presents seven oni stories from medieval Japan in full and translated for an English-speaking audience. Reider, concordant with many scholars of Japanese cultural studies, argues that to study oni is to study humanity. These tales are from an era in which many new oni stories appeared for the purpose of both entertainment and moral/religious edification and for which oni were particularly important, as they were perceived to be living entities. They reflect not only the worldview of medieval Japan but also themes that inform twenty-first-century Japanese pop and vernacular culture, including literature, manga, film, and anime. With each translation, Reider includes an introductory essay exploring the historical and cultural importance of the characters and oni manifestations within this period. Offering new insights into and interpretations of not only the stories therein but also the entire genre of Japanese ghost stories, Seven Demon Stories is a valuable companion to Reider’s 2010 volume Japanese Demon Lore. It will be of significant value to folklore scholars as well as students of Japanese culture.