The wind takes the pull of blood and meat away as they leave Karra with her kill, and the Doctor's scent soon fills Ace's nose instead. Her stomach growls, newly sharp fangs prick at her lip. She is agonizingly hungry, but it is deeper instinct, more powerful than mere loyalty and affection, that holds her to herself now.
It would not be a good hunt. He would not panic, running for her to chase until his lungs ached and his feet bled.
The Doctor's scent may be prey, but he is a predator more dangerous than any of her kind.