There are real live dogs in this world whose desire to be filled with their owners' presence, and even personality (if not that of humanity at large), is seemingly without limit. They just can't get enough of what is at least generously esteemed to be a good thing. It's not, so far as we know, that they want to stop being dogs. But they especially seem to relish having that doghood augmented or supplemented by whatever additional nature is on offer from the nearest caring human. Neither are all of them, by a long shot, canines of a selfish, demanding or petulant disposition. Many aren't just temperamentally "needy," as the expression goes, but can be quite usefully nice - at times, even in a surprising variety of mixed companies. Nor are their owners uniformly scroungy or contemptible. In fact, as often as not, both sides seem to make out quite well from the transaction.
Right. Now if only we human canines could desire to be thus usefully filled with our particular Owner . . .