Karin took part in the Chūnin Exams that were held in Konoha in Part I. During the second phase, taking place in the Forest of Death, she lost track of her team-mates and was attacked by a large bear. She was saved by Sasuke Uchiha who was disappointed to find she had the earth scroll as well, but she was able to catch a good glimpse of him before he left. She remembered the smile that Sasuke gave her.[2] According to the third Naruto databook, Karin lived in a small village that was burnt to the ground during a war. She was the only survivor, completely unharmed. Orochimaru found her after and asked how she survived, to which she answered that she could tell that huge groups of people were coming. Orochimaru then brought her to Otogakure, where she served as a jailer at one of his bases.[1] Unlike the rest of Taka, Karin was genuinely loyal to Orochimaru, going as far as to refuse to release Orochimaru's prisoners and, in the anime only, having them killed for speaking of his death, even after his defeat.Karin has a fluctuating personality; she will appear tough and in control at times, to the point of being violent and critical, and at other times will appear highly flirtatious. She annoys Suigetsu Hōzuki, whom she attacks whenever he voices his general opinion of her. She seems to be attracted to men based on their chakra level, and claims that Suigetsu's chakra disgusts her. Sasuke Uchiha's chakra used to dazzle her, but it now scares her, due to it getting colder and darker from his hatred. Naruto Uzumaki's seems to calm and dazzle her as well, making her feel comfortable and relaxed due to it being warm and bright, though she also became scared after sensing the Nine-Tailed Demon Fox's chakra.Karin has been praised by Madara Uchiha as being "helpful" for her abilities, and why Orochimaru adopted her after he found her. Despite being a mostly non-combatant, Orochimaru had faith in her enough to safeguard the Southern Hideout since her abilities made escaping practically impossible. Her special ability, the Mind's Eye of the Kagura, allows her to track specific individuals through chakra simply by using her standard concentration pose for moulding chakra. Sasuke noted her ability to sense chakra is unlike anyone else's. For example, she was once able to discern that Jūgo was not among a crowd of prisoners by chakra alone. It also allows her to pick up chakra from long distances, and notice changes in an individual's chakra. Kakashi Hatake surmised that Karin is a particularly skilled chakra-sensing ninja, as she is not only able to tell that his group is approaching, but can also sense how many of them are present, and that one is a dog.
She can also use her ability to determine if someone is lying by the fluctuations in that person's chakra made from dishonest emotions.[3] She can also find out if an enemy is using a clone jutsu and indicate if someone, including herself, is trapped in genjutsu. She can, similarly, conceal her own chakra from others.[4] However, doing so will render her unable to use chakra, thus disabling her Mind's Eye of the Kagura technique.