The first thing that stands out about your question is that you are more concerned with figuring out what your boss wants from you, rather than focusing on what you want for yourself. It sounds as though you want to maintain a friendship and nothing more. If this is your wish, then you must remain true to yourself. If you stay true to your core, then you will soon see that what he wants is immaterial.
Think of yourself as captain of a ship (the ship being your self). Never allow anyone to divert you from the course that you have established for yourself. If you want a friendship and nothing more, then follow your course. It sounds as if this man has other intentions. He seems to be courting you, and if you allow him to continue in this vein, without clarifying your position, like could become quite akward. Not to mention the fact that your job could be in jeopardy if he feels that you led him on by going along with his various courtship efforts.
You need to decide how you want to handle this. Do you want to be up front and tell him what you want from the relationship (that he is a lovely man and that you want his friendship)? Do you want to wait until he puts the moves on you and risk his utter humiliation and possible retaliation? Do you want to take a middle of the road approach and ask him to clarify his intentions? However you choose to deal with this sticky situation, make sure that you choose an option that feels right for you. Best wishes.