This is just a shame.

First you never close the door to his office again. If he asks you to do so, you tell him that is not appropriate and walk out. If he threatens your job, tell him you will file a sexual harassment suit. Waitress jobs are plentiful, you don't need one like that. Talk to the owner and tell her that he is risking her being sued.

I agree about the door - plus letting him take your hand and get close to you. AND there was no need to play dumb. He doesn't sound like a man who would do anything against your will. So be more distant from now on, and no more pleasant chat. Just business. This may not be the first time in your life, so practice now. I wasn't even all that attractive and I had my share of such people when I was young.

Just remember, you don't 'stand your ground ' with man like this. At the first 'come on' you are out the door and gone.