Hailing from the Benin Empire, Achoja serves as a shaman in a mercenary group employed by Abraham to capture Saki. He bears long black hair, yellow eyes, and scars across his face, arms, and legs, accessorized by a golden diadem and green beads adorning his neck and arms. Financially motivated, he accepts any sufficiently lucrative task. His group locates Saki but encounters Yasuke, another Black individual, prompting speculation about their connection. Yasuke breaks Achoja's nose during their clash before Saki incapacitates the entire group. Later, Nikita tracks Yasuke to a village bar where Abraham demands his capture alive. Seeking retribution, Achoja attacks Yasuke with a blade but is halted by Haruto. The mercenaries subdue and imprison Yasuke. While Abraham tortures Yasuke, Achoja initially shares Ishikawa’s skepticism about Yasuke’s endurance but intervenes, pulling Abraham away and declaring Yasuke holds no useful information. When Nikita and Haruto return with Saki, she uses Haruto’s power to immobilize Achoja and Ishikawa. Yasuke kills Abraham. With their employer dead and no stake in Yasuke or Saki, Achoja retrieves payment from Abraham’s pockets before departing. Later, Saki telepathically offers Achoja’s group double pay to aid Yasuke’s faction against the Dark Army. They accept and join the battle. After victory, Achoja demands payment, surprising Morisuke, who honors Saki’s promise. During a subsequent larger assault, Ishikawa dies and Haruto self-destructs. Nikita stays to fight while others retreat. Achoja plans to accompany Yasuke and Saki against the Daimyo but remains to defend children and elders after Morisuke triples his fee. As the Dark Army storms the temple, Morisuke’s barrier protects them. Morisuke notes Achoja’s spiritual strength but criticizes his preference for offensive over defensive use. Achoja counters with a Benin proverb: "no matter how hard a shield is, a blade will pierce it eventually." When the Daimyo morphs soldiers into a colossal monster to breach the barrier, Achoja channels his energy into it, reshaping it into a giant spirit warrior. Though overwhelmed initially, he survives the monster’s disintegration. He later receives substantial gold as payment. Achoja’s spiritual abilities summon two distinct combat spirits—one male, one female—to fight for him.