Robin Mask is a prominent character in the Kinnikuman series, known as one of the Choujin supermen. He is a noble, valiant, and honorable warrior hailing from the United Kingdom, and he often dons a knight-like armor. Robin Mask initially appears as an antagonist but eventually becomes one of the main allies of the protagonist, Kinnikuman. His character is well-respected among the Choujin due to his strong sense of justice, strategic mind, and formidable combat skills. Throughout the series, he plays a significant role in various battles and tournaments, showcasing his dedication to the Choujin cause.