Age: 14 Riko Amanai is probably a second-year in junior high. She was a student at Renchoku Girls' Junior High and the designated Star Plasma Vessel for Master Tengen's merger in 2006. When Riko was four years old, her parents were killed in a car accident, and she was taken care of by Misato Kuroi from then on. (Source: Jujutsu Kaisen Official Fanbook and Jujutsu Kaisen Wiki, edited)