ロマンチックジャーニイ　旅立ち (1986)

A salaryman, Aisuke, was molested by an older man on a crowded commuter train. He couldn't forget the excitement and started looking for the man every morning. When he finally found the man, he approached him, but he said he didn't know anything about him. When he finally finds the man, he tells him that he doesn't know anything about him, but he's not convinced, so he follows him...