Hentai

Hentai (変態 or へんたい)  listen  English /ˈhɛntaɪ/ is a word of Japanese origin which is short for (変態性欲^?, hentai seiyoku); a perverse sexual desire. The original meaning of Hentai in Japanese Language is a transformation or a metamorphosis. A meaning of the perversion or the paraphilia was derived from there. Both meanings can be distinguished in the context easily.

In Japanese, the term describes any type of perverse or bizarre sexual desire or act; it does not represent a genre of work. Internationally, hentai is a catch-all term to describe a genre of anime and manga pornography. English adopts and uses hentai as a genre of pornography by the commercial sale and marketing of explicit works under this label.

The word's narrow Japanese-language usage and broad international usage are often incompatible. Weather Report Girl is considered yuri hentai in English usage for its depiction of lesbian sex, but in Japan it is just yuri. The definition clash also appears with the Japanese definition of yuri as any lesbian relationship, as opposed to its sexually explicit definition in English usage.

https://en.wikipedia.org/wiki/Hentai