On the other hand, The Oxford Dictionary Online defines it as “a subgenre of the Japanese genres of manga and anime, characterized by overtly sexualized characters and sexually explicit images and plots.” The origin of the word in English is unknown, but AnimeNation’s John Oppliger points to the early 1990s, when a Dirty Pair erotic doujinshi (self-published work) titled H-Bomb was released, and when many websites sold access to images culled from Japanese erotic visual novels and games. Usage of the term hentai does not define a genre in Japan. The character hen is a catch-all for queerness as a peculiarity-it does not carry an explicit sexual reference. It is the shortened form of the phrase hentai seiyoku (変態性欲) which means “sexual perversion”.
It also means “perversion” or “abnormality”, especially when used as an adjective. In Japan, the term “hentai” is a kanji compound of 変 ( hen “change”, “weird”, or “strange”) and 態 ( tai “appearance” or “condition”).