Animated pornography is a very popular field.
When I first saw a video like that i was very surprised, but it is rather amusing too, In anime films, particularly "hentai" (google it) they actually usually have very in depth complicated story lines usually scifi/crime that interweaves graphic often oddball sex acts.
Dont knock it til you tried it!
I wouldnt call it arousing, but it sure beats Elmer Fudd, even when he was fat