dean would like to be called with the same pet names he has called women un the past.
he likes to cook, he likes to clean, he likes to be in charge in his house, but he really does not want to control the rest of his life. so cas would do that for him. at first cas does not get it, he can't understand why dean would want him to control the rest of his life. dean likes his free will, and he's decided to give that to castiel, he wants to be cared of, to be holded, and protected in ways he hadnt before. and cas is the right person (man) to do that. he trusts cas like that, with his own life.
he knows that cas will make the best choices for deans health.