I sometimes wonder what a live action adaptation of an ecchi manga looks like.  Yarukkya Knight (Blu-ray release 2015-7-15) provides this answer.  Adapted from Yarukkya Kishi, this movie begins with a transfer student who finds out that the new school is ruled by girls, with a rule that disallows boys from having an erection.  He decides to rebel against it.  Then a hentai teacher appears as the villain, causing the boys and girls to unite.

This PG12-rated movie tones down the ecchi severely, but doing this changes the essence of the original manga.  The prologue looks fairly interesting, but what remains is lifting up girls’ skirts – there are lots of such scenes, and unfortunately the movie becomes a one-trick pony.  Unless one is especially thrilled by such things, this ecchi comedy is average, because it quickly runs out of ideas for generating laughs.