Groper Train: Target the Impossible Woman (1999)

Kenichi, a student at a cram school, witnesses a young office lady being attacked on a crowded train. Kenichi musters up his courage and helps the lady. However, the lady yells at him for taking away her fun. From then on, Kenichi rides crowded trains every day in search of thrills. One day, a tough-looking man grabs his arm...