Atsuko Aimi appeared when the nine tails attacked the leaf and later sealed Atsuko Aimi was born with the Mask on he/she's face also with a piece of paper saying "Secrets can never be reveal to anyone" so Atsuko Aimi was raised under Danzō root division for most of her life to feel no emotion, feel no attachment, and to fear nothing. During he/she's stay in the Root Organization, Atsuko Aimi has been training on his/her Wood Release abilities along with "Kinoe" under danzo's watch for several years til Atsuko Aimi Left Root and later was adopted by the Hyuga Clan main branch.