This has nothing to do with submissiveness; it has everything to do with you are a woman who is being harassed and you don't feel safe. Who cares why? Not important. You need to make youself feel safe, you have every right to feel safe, and never, ever let anybody tell you that it is "wrong" or "overreacting" for you to do so. As a woman, you have to trust your instincts, because that is all we've got to protect us. You don't like him, you don't trust him, and you don't have to. If it was me, I would find a new way to get to work; or perhaps find a friend to walk with you. That would be my personal solution; and I am a very confident, self-assured, outspoken woman with no qualms about speaking my mind to anybody. And I would choose the most passive option available, because I don't want to find out who this guy is. I don't care. I just want to feel safe. And so should you.