Demon of the Ocean

The legend of the Sea Country states that anyone who is spotted on the shore of Demon Island, will disappear. It turns out that a test subject of Orochimaru named Isuribi, kidnapped those reported missing and presumed tested on forbidden jutsus. Orochimaru promised to turn her back into her true form, only if she does her part. In the end Orochimaru tricked her and didn't grant her her wish. Instead Naruto was able to show her his pain when he was younger and she understood that friends mean more then what other people think. She remained the "Demon of the Ocean".