Oopa, a human from Jananda, was sold by her parents for a single silver coin. She joined Tonari's group on Jananda Island, marked by a black cloth worn around the right wrist. Her appearance included long dark hair, a bandanna covering her right eye, a long-sleeved white shirt, a yellow jacket, and tan pants. She utilized poisoned blow darts defensively. Quiet, kind, and generous, Oopa once procured cow's blood to congratulate another character. She also displayed protective resolve, threatening to use her darts against those harassing Tonari. Oopa participated in Jananda's gladiatorial events. During the island's Nokker attack, she fought alongside Tonari's group in defense. Oopa perished in this conflict, alongside two other group members, while aiding Fushi's escape from Hayase. Her dream was to discover the sun's origin, a dream fulfilled posthumously. Her character arc is confined solely to the Jananda Island events.