Hentai is much more ethical than "normal", live-action porn. No human trafficking, no drug addictions, no STDs. Live-action porn is imperfect by definition; it stars humans, and one of the defining traits of humanity is imperfectness. Hentai, on the other hand, is much closer to perfection; it does not include any unwanted elements that are always present in people. Still the majority of people view hentai as sick or weird, even though it is much closer to perfection than live-action porn. The usual arguments against hentai are ones about the weirdness of being attracted and aroused at drawings. This is of no argumental value as it plays on the majority-ruled and zeitgeist dependent notion of "weirdness". What's weird is not universal; people of different cultural backgrounds may view things that other cultures do as sick or weird. In fact, it is much more abnormal to not be aroused by hentai, as hentai is the crystallization, the minimalistic arrangement of arousing qualities stripped of everything unnecessary. It is much more abnormal to not be aroused at these qualities that chosen specifically to arouse, than it is to be aroused at a random arrangement of genes transformed by random events through life. The same points also apply to virtual idols and singers such as Hatsune Miku and others like her. The inevitable impossibility of ever having physical contact with Hatsune Miku is no different from real singers; you as a normal person will most likely never touch her, the star.