Harry's seen people under the control of others; vampire thralls, humans enchanted by faeries, personalities dominated by demons or worse. There's a sort of vacantness in their eyes that he sees reflected in Yin's and it gives him pause. He's not sure if those situations would describe Yin's, or even if that control was something she faced here or at home, but he was leaning toward the latter.

She seemed completely out of her depth.

"Yeah? How so?"