Do users get a notification when I follow/unfollow them?

Hi,   I recently unfollowed a friend. Then followed back, but I do not longer see his activity on the right side of the screen. What's going on? He's just not active right now, he blocked me..? Does he get notifications when I follow or unfollow him?   Thanks    

If so, noone will be able to see what he is listening to. And to answer your question in the topic, you won't be noticed if a person follow/unfollow ...

Lee mas