Yoneya Yōsuke first appeared alongside Shūji Miwa investigating a trion soldier that had appeared in the Forbidden Zone. He remarked that whoever killed the trion soldier had to of been from A-Class. Yōsuke appeared again, helping Miwa stake out Osamu’s home. Yōsuke noted how pumped he was at the idea of fighting a humanoid neighbor, to which Miwa scolded him. Jin Yūichi appeared at that moment with orders from headquarters about an important mission.