I just remembered something. LOL
Ivan was teasing Cassie one day and Cassie was in a bad mood and just wanted to be left alone. She finally grabbed hold of his lip and wouldn't let go. Ivan carried her all the way across the room yelping all the way.
She didn't do any damage but he stopped messing with her.
I think the only thing you really have to worry about is those big feet! Your yorkie will have to learn to avoid them.