Yoko is shown to be very mature and knowledgeable for her age. Instead of being impulsive like Kamina, Yoko prefers to think things through before charging into battle. This preference, however, makes the two of them fight constantly. Yoko is known to be a very protective person, especially towards the people she cares about.
Awesome cosplay! I’m guessing she was attending a convention since she's wearing an ID. I just wonder from which one? Thanks to Adella for sending this in!