Mateus Callaway is a supporting character appearing in the second season of Chaika - The Coffin Princess, titled Avenging Battle. He is a male wizard affiliated with the Gillette Corps, a field unit of the Kleemann Agency tasked with pursuing the Chaikas and recovering the remains of Emperor Arthur Gaz. His magical specialty lies in the ability to control creatures, using them as assets in combat and reconnaissance. His background prior to joining the Gillette Corps includes training as a monk, which lends him a disciplined and composed demeanor. This foundation shapes his approach to both magic and his duties, as he operates with a measured, methodical style. In the story, Callaway serves primarily as an antagonist force aligned with the larger organization hunting the protagonists, though his role is that of a supporting agent rather than a primary villain. His interactions within the Gillette squad highlight his competence and loyalty to the mission, and he works alongside other squad members to track and engage the Chaika parties. His abilities in creature control distinguish him from other wizards in the series, allowing him to summon and direct monsters in battle. Over the course of the Avenging Battle arc, Callaway remains a consistent, though not deeply explored, figure whose actions contribute to the escalating conflict over the emperor's remains. While his last name is not explicitly stated in the anime itself, he is identified as Callaway in supplementary materials, and his first name appears with several spelling variations across different sources.