Isabel sounds like a proper well mannered, yet daring slave. it also sounds like her mood changes often, going from shy to outgoing and angry. it seems like she cares alot for her fellow slaves. i also think that she has courageosly learned how to read, and slyly sneeks into the library. she seems like a person that would di all that she could to make sure something is right and that she cares alot for her family.