My ex is following me on twitter?

[Miss ELW]

So my ex who i broke up with three years ago (but we still kind of had a thing for about two years, he was complete D**k to me but i let him...my fault) and havent seen properly or spoken properly to in over a year has started following me on twitter.

I dont have any feelings for him anymore, im with somebody new and have been since February. I knew my ex was on twitter because i came across his account, but i didnt follow him. He hasnt said anything to me on twitter and i dont think that he will, .

Should i block him or leave him to it? If he has been through my pictures or ny tweets, unless he is stupid he will know i am with someone.