However you might ignore a little company called "Zen Pictures"; a company that produce this kind of movies at an industrial rate - I am talking about 20 movies+ per years....
So what's the point of watching stupid plot less unsubtitled Japanese upskirt karate galore? well, upskirt karate galore, I guess... (The Japanese word for "entertainment" is "panchira")
Their website is http://http://www.akiba-heroine.com/, they sale their stuff not as DVD but as download - with heavy DRM and anti copy gizmos that sucks and make them complicated to watch if you are not a Microsoft Windows user - Yet this is rather a useless effort as the movies are all over the Internet movie download websites. Strangely - although Zen Pictures movies does not contain any nudity and often feature child actors - you will find them mostly on JAV porn website, mixed with stuff from "GIGA"; a twin company making the same kind of movies by same director and sometime with same actors and actresses but this time with a lot of jap-style porn thrown in. Jap-style porn can be quite gross so be aware of this - I personnaly avoid them and make sure what I download is really a "Zen", not a "Giga"
Call me crazy but I love to watch Zen Pictures movies. That doesn't means they are good. Actually they are rather crappy (not as crappy an American blockbuster by Roland Emmerich mind you) but they are made with some passion, they often star Asami (movies staring Asami are never completely bad) and the action scenes are - most of the time but not always - well choregraphed.