Rei Uzumaki is a girl from Kusagakure who was "kidnapped" by Hidoi for her Uzumaki lineage. However this was unkown to Rei until Hidoi researched her special Uzumaki chakra which allowed her to heal people through mouth to mouth. Because of her special life force, Rei survived one of Hidoi's expiriments; giving her the Wood Release kekkei genkai. After being rescued by Ryuun Shukiro, before Hidoi could steal her body to obtain the Wood Release, she was brought back to Konohagakure, where she was adopted into the village, and became a member of Team Ayane. She developted feelings for Ryuun during the time she was his teammate and devoted her life to helping him in any way she can.