Neither out-ranked the other.

They seemed to rule co-equal, while all others bowed before them.
It is not true that to feed a dog is to win a dog's heart.

Never did Harley or Villa feed Jerry; yet it was to them he elected to belong, them he elected to love and serve rather than to the Japanese steward who regularly fed him.

For that matter, Jerry, like any dog, was able to differentiate between the mere direct food-giver and the food source.
That is, subconsciously, he was aware that not alone his own food, but the food of all on board found its source in the man and woman.

They it was who fed all and ruled all.