@lovelyluna A king of monsters ought to be the strongest monster so that it can suppress the others. Some kind of manipulation power might also qualify, but if there monster horde is composed of many types of monsters, simple strength would be far less complicated. Noir is nothing but a kitten.
@karappo maybe, like in other stories, cure is just concentrated love, or happy thoughts, and baby monsters are just imprinting on whoever cast it on them.