It has not been "bleached" or lost any meaning. It never meant anything to do with anime or manga in Japanese in the first place. It is a completely non-sensical borrowing. Japanese otaku burst into giggle fits when westerners use it.
Also, here's what to call it: "porn anime", "porn manga", "porn games". That's what "ero" means. No need to make up words when English has perfectly workable ones that describe the subject exactly already.