Jo doesn't look shocked. If anything she looks torn between two things: pissed and pleased. She doesn't even hesitate to launch herself fully at Sam.

Sam who is not a teenage girl. Sam who is a hunter who can damn well take his punches and his broken bones without whining and having his big pretty brother beat her up for it.

He might be twice her size and it might be a sickening (twist in her stomach of digust and glee) thing to think about launching herself at Sam of all people -- but this time, she isn't holding back.

She knows she wouldn't want Sam to if it was her.

"Get the fuck out of him, you bastard."