A pet human, however, is unable to do anything (Well, anything that requires concious thought) without first being told so by whoever owns the pet. You know, just like any other pet, except this one happens to be of the same species as you. Think "hypnotic trance" -- but without the hypnosis.
Wubbish!

I've got a pet dog, and four pet rats, and they are all very autonomous. They do lots of conscious thought, and if I tell them to do something, it's kind of random (and also depends on if I've got food at the time) whether they do it or not.
Definition according to Dictionary.com:
Pet
n.
1. An animal kept for amusement or companionship.
2. An object of the affections.
3. A person especially loved or indulged; a favorite: the teacher's pet.
adj.
1. Kept as a pet: a pet cat.
2.
1. Particularly cherished or indulged: a pet grandchild.
2. Expressing or showing affection: a pet name.
3. Being a favorite: a pet topic.
.... So it can include a person! B)