You have to make your own experience, to know this feeling.
Tuner barks other people, when he feels, I am not in the mood for them. He knows me very good, I guess. When I am quit, yes unself conscious, he protected me. Even he is so little, he barks against big dogs and many people. He has so much power.
I remember, when he first came home, he barked at me, coz I also did. haha
I didn't wanted any relationship to a pet again, after my cat was poisoned..
(A very sad story.)
But now I am happy he is here and also am very afraid to lose him.