[KN] said: Well, i thought that a youkai is just a living creature that has paranormal powers
Technically, a youkai (妖怪, which stands for 'bewitching apparition') is a class of supernatural Japanese creatures. They are mostly corporeal, but include phenomena as well, like the Yuki-onna (snow woman). Apart from youkai, Japanese folklore recognizes ghosts (yuurei) as well, but most other forms of supernatural 'horrors' (quotation marks necessary, these supernatural creatures may only be mischievous, or even benevolent if treated well), such as ascended animals (such as the nekomata and kitsune) and stuff coming to life on its 100th anniversary (tsukumogami, see Tatara Kogasa) are logged under the heading of youkai, but in separate subcategories.
ThunderBird said: Technically, a youkai (妖怪, which stands for 'bewitching apparition') is a class of supernatural Japanese creatures. They are mostly corporeal, but include phenomena as well, like the Yuki-onna (snow woman). Apart from youkai, Japanese folklore recognizes ghosts (yuurei) as well, but most other forms of supernatural 'horrors' (quotation marks necessary, these supernatural creatures may only be mischievous, or even benevolent if treated well), such as ascended animals (such as the nekomata and kitsune) and stuff coming to life on its 100th anniversary (tsukumogami, see Tatara Kogasa) are logged under the heading of youkai, but in separate subcategories.