The shakilkhan person has a lot of steem invested in Steem Power, so they have more resources when they push their weight around.
When I saw that they down-voted me, I looked at their history https://steemd.com/@shakilkhan and up-voted a lot of the more recent posts that they had down-voted, while I don't have as much steem power to put behind my votes, I wanted to do what I could to try and help undo what shakilkhan was doing to people.