Part of me want to say that she is telling him about her past because she really cares about him... but i think she is just doing it in case he tried to check her backgrounds and find out she was lying and then started suspecting her... she is 2 cunning in this is something she can easily do... but sometimes she shows a childish side to herself... like how she wrote those fantasy stories that actually have some information about the truth of the village @_@