Riko is a young slim girl with long dark hair that is braided in the back and extends past her shoulders, with her bangs extending down and covering the middle of her forehead. She is always seen with her light hairband on the top of her head and normally wore her school uniform. She was a student at Renchoku Girls' Junior High and the designated Star Plasma Vessel for Master Tengen's merger in 2006. She is good friends with Suguru Geto and Gojo Satoru. Riko is emotional and hyperactive.