You were itachi's sister and you had an amazing chakra, that's why Danzō put his eyes on you, manipulating you to fulfil his dark goals without anyone knowing. Thanks to your brother you developed a great bond with Shisui, starting to develop feelings for him, however, as Danzo was afraid of your power he threatened you to leave the village and join Akatsuki. Your life collapsed, but in order to protect Itachi and Shisui, you abandoned your whole life and became a wanted criminal.