What do you think about me making my fiancee cut all contact with a male friend because he sexually harasses her all the time?
What do you want her to say to him?
To stay the fuck away from her or to drop dead.
While is normally not good to try to control who your fiancee is friends with, it is not good for her to be friends with somebody who harassers her. It would be good for her to be apart from this person.
I don't care if she gets harassed, I just don't want her to keep any kind of contact with him.
It sounds like you do care if she gets harassed since you're making such a big deal out of this because of the harassment that he brings. You should at least tell her that you want her to have a conversation with him, and if he doesn't stop the harassment then you'll speak with him and cut all contact. It is wrong to harass people.