Hentai describes a type of animation with highly erotic, pornographic content. This word, originary from Japan, did not originally describe a type of media: it was instead an abbreviation of the word "hentai seiyoku" which means "sexual perversion", or an uncommon, bizarre sexual attraction to something out of the usual. Hentai has been a genre since Japanese animation was created, and it seems like their inception happened at almost the same time: Astroboy's creator also created highly pornographic sketches of humanoid characters with animal characteristics that were never compiled into a manga, and therefore never published. Hentai is pornographic in nature, and therefore just as varied as regular pornographic movies: we can find heterosexual hentai, but genres such as yuri (for woman on woman love) or "yaoi" (for men on men love) are also popular. Some other popular clichés in hentai are friends, school girls and boys, family relations and many other fetishes that are also popular in non animated pornography.