Dan Oniroku's Female Teacher (2005)

Kanako, a math teacher who had previously inflicted punishment on a student at her previous school, has now been appointed to Kuronuma High School after completing her atonement. However, soon after arriving, she is attacked by four delinquents from her class. She is taken to an abandoned factory site, where the students, who have photographed her naked and bound, take turns raping her. Yada gazes at the unconscious Kanako, who is being held up in the air, with a look of amusement. He flashes the photographic evidence of what happened at the factory site, bringing up the past punishment, and corners the defenceless Kanako, saying, "There is punishment for every crime." She resists desperately, but there is nothing she can do...