Zaphoid waits until you set something down on the bed and then lays on it so that you can't move it. Well, so does Thomas and Mister Kitten. This is a sacred duty. Star doesn't do this because he would rather use his Mutant Ninja Powers on getting more treats.
And so I suspect Da Boys. Either that or it's Gremlins. Okay boys, catch the Gremlins & tell them to bring my life!!