The realm only tolerates Earth due to its divine commission to keep an eye on us. It copes with having to do this by ensuring most on Earth have no idea of its existence so can't possibly threaten it in any way. It nicks our good ideas to save its own magical energy (though the Kingdom likes to think of this as recycling ideas).
Eileen is one of the few magical beings who does actually care for Earth and its inhabitants. It is one reason why she is thought to be somewhat odd by her former compatriots!
I hope at some point to write some stories about the interactions with other worlds. But the Kingdom definitely is not the innocent party at times. I would like to look at some point as to how the realm developed that attitude, whether anyone other than Eileen tried to go against this and if so what happened to them and why didn't they succeed?