Seong-je is described as being playful, not taking things too seriously, and having an air of arrogance and attitude around him. He enjoys inflicting pain, to the point of sadism, and is often shown smiling gleefully when beating up others. Seong-je has dark curtain cut hair that is layered, and is of medium length (bangs reaching his eyebrows). He has pale skin, is slim, tall, and wears half-rimmed glasses. Seong-je has incredible physical strength, durability, and speed. He primarily uses Boxing-like punches (in-fighter-out-fighter hybrid), and uses grounded kicks efficiently, rather than flashy ones. He can clinch, grapple minimally, and his style is influenced by street MMA

Na Baek-jin is a powerful fighter with unmatched strength. Even without using force, he has an intimidating presence that prevents others from challenging him. He is a strong, charismatic leader who achieves success. He makes quick decisions, allowing him to complete tasks efficiently. He also has a very high level of academic intelligence, nearly achieving a perfect score on an exam. He has black hair and black eyes.