Two comments. First, a lot of people use the term "blackmail" to cover a variety of situations that would not meet the usual legal definition of the term (in those places that still have blackmail as distinct crime). So it very much matters what the other person is doing, in what state/territory/district the American is located, and in what province/territory of Canada you reside. Second, you asked if there are any legal "repurcussions". Well, not knowing what the details are, I cannot guess what consequences his/her actions might have on you. If you meant to ask if you have any legal remedies for what the other person is doing, that too requires knowing what is going on. You might start by meeting with a Canadian lawyer to discuss it if you do not want to share details here.

