If I avoid the eye-contact of the guy who previously ually molested me will he think I fear him?

It sounds to me like you really enjoy thinking about and catching the attention of this guy. That surprises me because you describe him as being quite nasty to you. However, you did something to him that wasn't very nice, either. Maybe you two have a love-hate relationship. Perhaps you would be suited as a couple. I'm not making a joke, it really sounds to me as if you two are into each other, just not in a healthy way. If you really do dislike him, try to stop thinking about him. Don't talk to him or look his way in lectures. Sit so you can't see him. Make friends and speak to them in cl and force yourself to get your mind off of this man. It's time to accept him and make up or completely move on.