The goal of this paper is to introduce Japanese demonology. The paper focuses on the spirits known as yōkai, providing answers from the incredibly scarce publications in Polish covering issues related to Japanese demonology. The article examines the origin of the term yōkai and thedifferences in meaning between yōkai, mononoke and ayakashi. It goes on to explain the difference between yōkai and kami, as well as introducing a categorisation of spirits to explain how new yōkai are generated
