Groper Train Pleasure! Peach Butt Touch (2003)

Sakura, a nurse, has a boyfriend and is at the peak of happiness. However, Sakura has something to worry about. Her father, Tsurugirou, selfishly says that "molesting working women will reduce their stress and make Japan a better place," and goes out on crowded trains every day, ignoring his daughter's pleas to stop him. One day, her boyfriend has a revelation on the crowded train and tells Tsurugirou that he wants to become his apprentice...