“Once, in a village destroyed by the fires of war, a young girl stood, totally unscathed. She said, “I knew a lot of people were coming”. This is how Orochimaru came to bring Karin to Otogakure.
Karin began serving the Sound with her sharp sensory skills and clear thinking. However, although she was Orochimaru’s subordinate, she never felt any loyalty to him.
She continued because of her love for Sasuke.”
- Karin’s Databook Entry