Achoja hails from the Benin Empire in southern Nigeria, working as a shaman and mercenary driven chiefly by financial reward. He possesses long black hair, distinctive yellow eyes, and scars across his face, arms, and legs. His attire includes a golden diadem and green beads adorning his neck and arms. Hired by the priest Abraham, Achoja joins a team to capture Saki, a girl with supernatural powers. He demonstrates a pragmatic focus on payment, though he intervenes to halt Abraham's excessive torture of Yasuke when it proves futile. Achoja fights using spiritual abilities, summoning two combat spirits—one male and one female—to engage opponents. During the mission to find Saki, his group confronts Yasuke, resulting in Achoja sustaining a broken nose. After Abraham's death, he retrieves money from Abraham's body and departs with the other mercenaries, disengaging once payment is void. However, Saki contacts him telepathically later, offering doubled pay to fight the Dark Army. Achoja and his team agree, joining Yasuke and Morisuke's forces. In the battle against the Dark Daimyo's forces, Achoja witnesses the deaths of fellow mercenaries Ishikawa, Haruto, and Nikita. Defending Morisuke's temple, he significantly contributes by merging his spiritual powers with Morisuke's barrier abilities. Morisuke notes Achoja typically uses his powers offensively as a "weapon." Achoja counters with a Benin saying, "no matter how hard a shield is, a blade will pierce it eventually," then transforms the barrier into a colossal spirit fighter against a monster formed from enemy soldiers. Though overwhelmed, he survives the battle. Receiving triple payment from Morisuke afterward, he expresses satisfaction with the acquired gold.