After the Fūma clan finished a war with a neighbouring country, they wandered the Land of Rice Fields hoping to settle down. Near the end of their journey, Orochimaru and Kimimaro appeared before the Fūma and told them that if they joined Otogakure that Orochimaru would help in restoring their power. Kagerō agreed and left with them. Though she was actually a young girl, Kagerō constantly disguised herself as a grotesque, hunchbacked man with buck teeth. This transformation can't be dispelled even if she was wounded. While disguised as a man, she would use the Earth Release: Antlion Technique to cause everything in a certain area to be drawn into a large pit. She constantly made references to the life of a mayfly while in her male disguise, which makes sense, as "Kagerō" can mean "mayfly". Kagerō also shows deep appreciation for poetry as when in her male disguise she recited a short poem comparing herself to the mayfly before attempting to sink Naruto. She attempted to kill Naruto by synchronising their heartbeats and stopping hers, but Sakura cut the chakra threads connecting them with a seal obtained from Sasame, therefore freeing Naruto from Kagerō's attack.