LOL. It can't be done. Also you can't be kicked out of a kingdom.

Your kingdom has just opened for people to drakkar in and you should expect a bunch of jerks to show up and create havoc before they move on to play the same way in newer kingdoms.

You may see it as bullying but it is playing within the rules of the game and Plarium will not act against him for killing troops which is a part of their game while tile naps are a player tactic.

There is definitely something you can do and that is to frustrate him by providing few opportunities for him to attack. I have suggested this to other players in similar situations before and they say that it would ruin the game for them. It's your player's choice - develop strategies to work around this just as you worked out the nap or don't. I can't guarantee that he will go away but if you ignore him and don't give him chances for easy kills he will lose his current fun of baiting you.