Kinako is the only child of Orochimaru. She was used as a success experiment because ever since Orochimaru's adoptive parents died, He was sad and lonely. He wanted to learn more Justus because he wanted to teach it to Kinko so that she doesn't die. The reason why he wants immortality is that he wouldn't die and make Kinako sad and make her immortals so she could be forever his little girl. The reason why he ran away from Konoha is because he wanted Kinako safe from Konoha's clutches because they might make her a breeding stock

This is the story bout Orochimaru's daughter OK please read!